1
|
Haase MAB, Steenwyk JL, Boeke JD. Gene loss and cis-regulatory novelty shaped core histone gene evolution in the apiculate yeast Hanseniaspora uvarum. Genetics 2024; 226:iyae008. [PMID: 38271560 PMCID: PMC10917516 DOI: 10.1093/genetics/iyae008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024] Open
Abstract
Core histone genes display a remarkable diversity of cis-regulatory mechanisms despite their protein sequence conservation. However, the dynamics and significance of this regulatory turnover are not well understood. Here, we describe the evolutionary history of core histone gene regulation across 400 million years in budding yeasts. We find that canonical mode of core histone regulation-mediated by the trans-regulator Spt10-is ancient, likely emerging between 320 and 380 million years ago and is fixed in the majority of extant species. Unexpectedly, we uncovered the emergence of a novel core histone regulatory mode in the Hanseniaspora genus, from its fast-evolving lineage, which coincided with the loss of 1 copy of its paralogous core histone genes. We show that the ancestral Spt10 histone regulatory mode was replaced, via cis-regulatory changes in the histone control regions, by a derived Mcm1 histone regulatory mode and that this rewiring event occurred with no changes to the trans-regulator, Mcm1, itself. Finally, we studied the growth dynamics of the cell cycle and histone synthesis in genetically modified Hanseniaspora uvarum. We find that H. uvarum divides rapidly, with most cells completing a cell cycle within 60 minutes. Interestingly, we observed that the regulatory coupling between histone and DNA synthesis was lost in H. uvarum. Our results demonstrate that core histone gene regulation was fixed anciently in budding yeasts, however it has greatly diverged in the Hanseniaspora fast-evolving lineage.
Collapse
Affiliation(s)
- Max A B Haase
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, 435 E 30th St, New York, NY 10016, USA
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Jacob L Steenwyk
- Howards Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Jef D Boeke
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, 435 E 30th St, New York, NY 10016, USA
| |
Collapse
|
2
|
Jafarpour F, Levien E, Amir A. Evolutionary dynamics in non-Markovian models of microbial populations. Phys Rev E 2023; 108:034402. [PMID: 37849168 DOI: 10.1103/physreve.108.034402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 06/07/2023] [Indexed: 10/19/2023]
Abstract
In the past decade, great strides have been made to quantify the dynamics of single-cell growth and division in microbes. In order to make sense of the evolutionary history of these organisms, we must understand how features of single-cell growth and division influence evolutionary dynamics. This requires us to connect processes on the single-cell scale to population dynamics. Here, we consider a model of microbial growth in finite populations which explicitly incorporates the single-cell dynamics. We study the behavior of a mutant population in such a model and ask: can the evolutionary dynamics be coarse-grained so that the forces of natural selection and genetic drift can be expressed in terms of the long-term fitness? We show that it is in fact not possible, as there is no way to define a single fitness parameter (or reproductive rate) that defines the fate of an organism even in a constant environment. This is due to fluctuations in the population averaged division rate. As a result, various details of the single-cell dynamics affect the fate of a new mutant independently from how they affect the long-term growth rate of the mutant population. In particular, we show that in the case of neutral mutations, variability in generation times increases the rate of genetic drift, and in the case of beneficial mutations, variability decreases its fixation probability. Furthermore, we explain the source of the persistent division rate fluctuations and provide analytic solutions for the fixation probability as a multispecies generalization of the Euler-Lotka equation.
Collapse
Affiliation(s)
- Farshid Jafarpour
- Institute for Theoretical Physics, Utrecht University, 3584 CC Utrecht, The Netherlands
| | - Ethan Levien
- Mathematics Department, Dartmouth College, Hanover, New Hampshire 03755, USA
| | - Ariel Amir
- Department of Complex Systems, Faculty of Physics, The Weizmann Institute of Science, Rehovot 7610001, Israel
- John A. Paulson, School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| |
Collapse
|
3
|
Li R, Rozum JC, Quail MM, Qasim MN, Sindi SS, Nobile CJ, Albert R, Hernday AD. Inferring gene regulatory networks using transcriptional profiles as dynamical attractors. PLoS Comput Biol 2023; 19:e1010991. [PMID: 37607190 PMCID: PMC10473541 DOI: 10.1371/journal.pcbi.1010991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 09/01/2023] [Accepted: 07/19/2023] [Indexed: 08/24/2023] Open
Abstract
Genetic regulatory networks (GRNs) regulate the flow of genetic information from the genome to expressed messenger RNAs (mRNAs) and thus are critical to controlling the phenotypic characteristics of cells. Numerous methods exist for profiling mRNA transcript levels and identifying protein-DNA binding interactions at the genome-wide scale. These enable researchers to determine the structure and output of transcriptional regulatory networks, but uncovering the complete structure and regulatory logic of GRNs remains a challenge. The field of GRN inference aims to meet this challenge using computational modeling to derive the structure and logic of GRNs from experimental data and to encode this knowledge in Boolean networks, Bayesian networks, ordinary differential equation (ODE) models, or other modeling frameworks. However, most existing models do not incorporate dynamic transcriptional data since it has historically been less widely available in comparison to "static" transcriptional data. We report the development of an evolutionary algorithm-based ODE modeling approach (named EA) that integrates kinetic transcription data and the theory of attractor matching to infer GRN architecture and regulatory logic. Our method outperformed six leading GRN inference methods, none of which incorporate kinetic transcriptional data, in predicting regulatory connections among TFs when applied to a small-scale engineered synthetic GRN in Saccharomyces cerevisiae. Moreover, we demonstrate the potential of our method to predict unknown transcriptional profiles that would be produced upon genetic perturbation of the GRN governing a two-state cellular phenotypic switch in Candida albicans. We established an iterative refinement strategy to facilitate candidate selection for experimentation; the experimental results in turn provide validation or improvement for the model. In this way, our GRN inference approach can expedite the development of a sophisticated mathematical model that can accurately describe the structure and dynamics of the in vivo GRN.
Collapse
Affiliation(s)
- Ruihao Li
- Quantitative and Systems Biology Graduate Program, University of California, Merced, Merced, California, United States of America
| | - Jordan C. Rozum
- Department of Systems Science and Industrial Engineering, Binghamton University (State University of New York), Binghamton, New York, United States of America
| | - Morgan M. Quail
- Quantitative and Systems Biology Graduate Program, University of California, Merced, Merced, California, United States of America
| | - Mohammad N. Qasim
- Quantitative and Systems Biology Graduate Program, University of California, Merced, Merced, California, United States of America
| | - Suzanne S. Sindi
- Department of Applied Mathematics, University of California, Merced, Merced, California, United States of America
| | - Clarissa J. Nobile
- Department of Molecular Cell Biology, University of California, Merced, Merced, California, United States of America
- Health Sciences Research Institute, University of California, Merced, Merced, California, United States of America
| | - Réka Albert
- Department of Physics, Pennsylvania State University, University Park, University Park, Pennsylvania, United States of America
- Department of Biology, Pennsylvania State University, University Park, University Park, Pennsylvania, United States of America
| | - Aaron D. Hernday
- Department of Molecular Cell Biology, University of California, Merced, Merced, California, United States of America
- Health Sciences Research Institute, University of California, Merced, Merced, California, United States of America
| |
Collapse
|
4
|
Del Frate F, Garber ME, Johnson AD. Evolution of a new form of haploid-specific gene regulation appearing in a limited clade of ascomycete yeast species. Genetics 2023; 224:iyad053. [PMID: 37119800 PMCID: PMC10484167 DOI: 10.1093/genetics/iyad053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 01/09/2023] [Accepted: 03/13/2023] [Indexed: 05/01/2023] Open
Abstract
Over evolutionary timescales, the logic and pattern of cell-type specific gene expression can remain constant, yet the molecular mechanisms underlying such regulation can drift between alternative forms. Here, we document a new example of this principle in the regulation of the haploid-specific genes in a small clade of fungal species. For most ascomycete fungal species, transcription of these genes is repressed in the a/α cell type by a heterodimer of two homeodomain proteins, Mata1 and Matα2. We show that in the species Lachancea kluyveri, most of the haploid-specific genes are regulated in this way, but repression of one haploid-specific gene (GPA1) requires, in addition to Mata1 and Matα2, a third regulatory protein, Mcm1. Model building, based on x-ray crystal structures of the three proteins, rationalizes the requirement for all three proteins: no single pair of the proteins is optimally arranged, and we show that no single pair can bring about repression. This case study exemplifies the idea that the energy of DNA binding can be "shared out" in different ways and can result in different DNA-binding solutions across different genes-while maintaining the same overall pattern of gene expression.
Collapse
Affiliation(s)
- Francesca Del Frate
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94102, USA
- Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94102, USA
| | - Megan E Garber
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94102, USA
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94102, USA
- Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94102, USA
| |
Collapse
|
5
|
Mechanisms of regulatory evolution in yeast. Curr Opin Genet Dev 2022; 77:101998. [PMID: 36220001 PMCID: PMC10117219 DOI: 10.1016/j.gde.2022.101998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 02/06/2023]
Abstract
Studies of regulatory variation in yeast - at the level of new mutations, polymorphisms within a species, and divergence between species - have provided great insight into the molecular and evolutionary processes responsible for the evolution of gene expression in eukaryotes. The increasing ease with which yeast genomes can be manipulated and expression quantified in a high-throughput manner has recently accelerated mechanistic studies of cis- and trans-regulatory variation at multiple evolutionary timescales. These studies have, for example, identified differences in the properties of cis- and trans-acting mutations that affect their evolutionary fate, experimentally characterized the molecular mechanisms through which cis- and trans-regulatory variants act, and illustrated how regulatory networks can diverge between species with or without changes in gene expression.
Collapse
|
6
|
Mating-Type Switching in Budding Yeasts, from Flip/Flop Inversion to Cassette Mechanisms. Microbiol Mol Biol Rev 2022; 86:e0000721. [PMID: 35195440 PMCID: PMC8941940 DOI: 10.1128/mmbr.00007-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mating-type switching is a natural but unusual genetic control process that regulates cell identity in ascomycete yeasts. It involves physically replacing one small piece of genomic DNA by another, resulting in replacement of the master regulatory genes in the mating pathway and hence a switch of cell type and mating behavior. In this review, we concentrate on recent progress that has been made on understanding the origins and evolution of mating-type switching systems in budding yeasts (subphylum Saccharomycotina). Because of the unusual nature and the complexity of the mechanism in Saccharomyces cerevisiae, mating-type switching was assumed until recently to have originated only once or twice during yeast evolution. However, comparative genomics analysis now shows that switching mechanisms arose many times independently-at least 11 times in budding yeasts and once in fission yeasts-a dramatic example of convergent evolution. Most of these lineages switch mating types by a flip/flop mechanism that inverts a section of a chromosome and is simpler than the well-characterized 3-locus cassette mechanism (MAT/HML/HMR) used by S. cerevisiae. Mating-type switching (secondary homothallism) is one of the two possible mechanisms by which a yeast species can become self-fertile. The other mechanism (primary homothallism) has also emerged independently in multiple evolutionary lineages of budding yeasts, indicating that homothallism has been favored strongly by natural selection. Recent work shows that HO endonuclease, which makes the double-strand DNA break that initiates switching at the S. cerevisiae MAT locus, evolved from an unusual mobile genetic element that originally targeted a glycolytic gene, FBA1.
Collapse
|
7
|
Solieri L, Cassanelli S, Huff F, Barroso L, Branduardi P, Louis EJ, Morrissey JP. Insights on life cycle and cell identity regulatory circuits for unlocking genetic improvement in Zygosaccharomyces and Kluyveromyces yeasts. FEMS Yeast Res 2021; 21:foab058. [PMID: 34791177 PMCID: PMC8673824 DOI: 10.1093/femsyr/foab058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/14/2021] [Indexed: 11/14/2022] Open
Abstract
Evolution has provided a vast diversity of yeasts that play fundamental roles in nature and society. This diversity is not limited to genotypically homogeneous species with natural interspecies hybrids and allodiploids that blur species boundaries frequently isolated. Thus, life cycle and the nature of breeding systems have profound effects on genome variation, shaping heterozygosity, genotype diversity and ploidy level. The apparent enrichment of hybrids in industry-related environments suggests that hybridization provides an adaptive route against stressors and creates interest in developing new hybrids for biotechnological uses. For example, in the Saccharomyces genus where regulatory circuits controlling cell identity, mating competence and meiosis commitment have been extensively studied, this body of knowledge is being used to combine interesting traits into synthetic F1 hybrids, to bypass F1 hybrid sterility and to dissect complex phenotypes by bulk segregant analysis. Although these aspects are less known in other industrially promising yeasts, advances in whole-genome sequencing and analysis are changing this and new insights are being gained, especially in the food-associated genera Zygosaccharomyces and Kluyveromyces. We discuss this new knowledge and highlight how deciphering cell identity circuits in these lineages will contribute significantly to identify the genetic determinants underpinning complex phenotypes and open new avenues for breeding programmes.
Collapse
Affiliation(s)
- Lisa Solieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Stefano Cassanelli
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Franziska Huff
- School of Microbiology, APC Microbiome Ireland, Environmental Research Institute, University College Cork, Cork T12 K8AF, Ireland
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Liliane Barroso
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
- Department of Biotechnology and Biosciences, University of Milano Bicocca, Piazza della Scienza, 2-20126 Milano, Italy
| | - Paola Branduardi
- Department of Biotechnology and Biosciences, University of Milano Bicocca, Piazza della Scienza, 2-20126 Milano, Italy
| | - Edward J Louis
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | - John P Morrissey
- School of Microbiology, APC Microbiome Ireland, Environmental Research Institute, University College Cork, Cork T12 K8AF, Ireland
| |
Collapse
|
8
|
Ogata T, Kuroki K. Regulation of mating and mating-type-specific genes in Zygosaccharomyces sp. yeast. Yeast 2021; 38:471-479. [PMID: 33811363 DOI: 10.1002/yea.3561] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/16/2021] [Accepted: 03/26/2021] [Indexed: 11/11/2022] Open
Abstract
Zygosaccharomyces sp. is an industrially important yeast for the production traditional fermented foods in Japan. At present, however, there is no easy method for mating Zygosaccharomyces sp. strains in the laboratory; furthermore, little is known about the expression of mating-type-specific genes in this yeast. Here, mating was observed when Zygosaccharomyces sp. was subjected to nitrogen-starvation conditions. The expression of mating-type-specific genes, Zygo STE6 and Zygo MFα1, was induced under nitrogen-starvation conditions, as confirmed by lacZ reporter assay. This expression was mating-type-specific: Zygo STE6 was expressed specifically for mating-type a, whereas and Zygo MFα1 was expressed specifically for mating-type α. Yeast strains Zygosaccharomyces rouxii DL2 and DA2, derived from type strain Z. rouxii CBS732, did not show mating even under nitrogen-starvation conditions. Gene sequencing revealed that the Zygo STE12 in Z. rouxii CBS732 has a frameshift mutation. Under nitrogen starvation, mating was observed in both DL2 and DA2 transformed with the wild-type Zygo STE12. The expression of Zygo STE6 in Z. rouxii DL2 transformed with wild-type Zygo STE12 under nitrogen-starvation conditions was confirmed by lacZ reporter assay. Collectively, these results revealed that, under nitrogen-starvation conditions, Zygosaccharomyces sp. can mate and mating-type-specific genes are expressed. Furthermore, Zygo Ste12 is essential for both mating and the expression of mating-type-specific genes in Zygosaccharomyces sp.
Collapse
Affiliation(s)
- Tomoo Ogata
- Department of Biotechnology, Maebashi Institute of Technology, Maebashi, Japan
| | - Katsuaki Kuroki
- Department of Biotechnology, Maebashi Institute of Technology, Maebashi, Japan
| |
Collapse
|
9
|
Escudero JA, Nivina A, Kemble HE, Loot C, Tenaillon O, Mazel D. Primary and promiscuous functions coexist during evolutionary innovation through whole protein domain acquisitions. eLife 2020; 9:58061. [PMID: 33319743 PMCID: PMC7790495 DOI: 10.7554/elife.58061] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 12/14/2020] [Indexed: 11/13/2022] Open
Abstract
Molecular examples of evolutionary innovation are scarce and generally involve point mutations. Innovation can occur through larger rearrangements, but here experimental data is extremely limited. Integron integrases innovated from double-strand- toward single-strand-DNA recombination through the acquisition of the I2 α-helix. To investigate how this transition was possible, we have evolved integrase IntI1 to what should correspond to an early innovation state by selecting for its ancestral activity. Using synonymous alleles to enlarge sequence space exploration, we have retrieved 13 mutations affecting both I2 and the multimerization domains of IntI1. We circumvented epistasis constraints among them using a combinatorial library that revealed their individual and collective fitness effects. We obtained up to 104-fold increases in ancestral activity with various asymmetrical trade-offs in single-strand-DNA recombination. We show that high levels of primary and promiscuous functions could have initially coexisted following I2 acquisition, paving the way for a gradual evolution toward innovation.
Collapse
Affiliation(s)
- José Antonio Escudero
- Institut Pasteur, Unité de Plasticité du Génome Bactérien, Département Génomes et Génétique, Paris, France.,CNRS, UMR3525, Paris, France.,Molecular Basis of Adaptation, Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain.,VISAVET Health Surveillance Centre. Universidad Complutense Madrid. Avenida Puerta de Hierro, Madrid, Spain
| | - Aleksandra Nivina
- Institut Pasteur, Unité de Plasticité du Génome Bactérien, Département Génomes et Génétique, Paris, France.,CNRS, UMR3525, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Harry E Kemble
- Infection, Antimicrobials, Modelling, Evolution, INSERM, UMR 1137, Université Paris Diderot, Université Paris Nord, Paris, France
| | - Céline Loot
- Institut Pasteur, Unité de Plasticité du Génome Bactérien, Département Génomes et Génétique, Paris, France.,CNRS, UMR3525, Paris, France
| | - Olivier Tenaillon
- Infection, Antimicrobials, Modelling, Evolution, INSERM, UMR 1137, Université Paris Diderot, Université Paris Nord, Paris, France
| | - Didier Mazel
- Institut Pasteur, Unité de Plasticité du Génome Bactérien, Département Génomes et Génétique, Paris, France.,CNRS, UMR3525, Paris, France
| |
Collapse
|
10
|
Sporulation in Ashbya gossypii. J Fungi (Basel) 2020; 6:jof6030157. [PMID: 32872517 PMCID: PMC7558398 DOI: 10.3390/jof6030157] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/28/2022] Open
Abstract
Ashbya gossypii is a filamentous ascomycete belonging to the yeast family of Saccharomycetaceae. At the end of its growth phase Ashbya generates abundant amounts of riboflavin and spores that form within sporangia derived from fragmented cellular compartments of hyphae. The length of spores differs within species of the genus. Needle-shaped Ashbya spores aggregate via terminal filaments. A. gossypii is a homothallic fungus which may possess a and α mating types. However, the solo-MATa type strain is self-fertile and sporulates abundantly apparently without the need of prior mating. The central components required for the regulation of sporulation, encoded by IME1, IME2, IME4, KAR4, are conserved with Saccharomyces cerevisiae. Nutrient depletion generates a strong positive signal for sporulation via the cAMP-PKA pathway and SOK2, which is also essential for sporulation. Strong inhibitors of sporulation besides mutations in the central regulatory genes are the addition of exogenous cAMP or the overexpression of the mating type gene MATα2. Sporulation has been dissected using gene-function analyses and global RNA-seq transcriptomics. This revealed a role of Msn2/4, another potential PKA-target, for spore wall formation and a key dual role of the protein A kinase Tpk2 at the onset of sporulation as well as for breaking the dormancy of spores to initiate germination. Recent work has provided an overview of ascus development, regulation of sporulation and spore maturation. This will be summarized in the current review with a focus on the central regulatory genes. Current research and open questions will also be discussed.
Collapse
|
11
|
Belcher MS, Vuu KM, Zhou A, Mansoori N, Agosto Ramos A, Thompson MG, Scheller HV, Loqué D, Shih PM. Design of orthogonal regulatory systems for modulating gene expression in plants. Nat Chem Biol 2020; 16:857-865. [PMID: 32424304 DOI: 10.1038/s41589-020-0547-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 04/09/2020] [Indexed: 11/08/2022]
Abstract
Agricultural biotechnology strategies often require the precise regulation of multiple genes to effectively modify complex plant traits. However, most efforts are hindered by a lack of characterized tools that allow for reliable and targeted expression of transgenes. We have successfully engineered a library of synthetic transcriptional regulators that modulate expression strength in planta. By leveraging orthogonal regulatory systems from Saccharomyces spp., we have developed a strategy for the design of synthetic activators, synthetic repressors, and synthetic promoters and have validated their use in Nicotiana benthamiana and Arabidopsis thaliana. This characterization of contributing genetic elements that dictate gene expression represents a foundation for the rational design of refined synthetic regulators. Our findings demonstrate that these tools provide variation in transcriptional output while enabling the concerted expression of multiple genes in a tissue-specific and environmentally responsive manner, providing a basis for generating complex genetic circuits that process endogenous and environmental stimuli.
Collapse
Affiliation(s)
- Michael S Belcher
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Khanh M Vuu
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Andy Zhou
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant Biology, University of California, Davis, Davis, CA, USA
| | - Nasim Mansoori
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Amanda Agosto Ramos
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mitchell G Thompson
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant Biology, University of California, Davis, Davis, CA, USA
| | - Henrik V Scheller
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Dominique Loqué
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Patrick M Shih
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA.
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Plant Biology, University of California, Davis, Davis, CA, USA.
| |
Collapse
|
12
|
Britton CS, Sorrells TR, Johnson AD. Protein-coding changes preceded cis-regulatory gains in a newly evolved transcription circuit. Science 2020; 367:96-100. [PMID: 31896718 DOI: 10.1126/science.aax5217] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 11/05/2019] [Indexed: 12/26/2022]
Abstract
Changes in both the coding sequence of transcriptional regulators and in the cis-regulatory sequences recognized by these regulators have been implicated in the evolution of transcriptional circuits. However, little is known about how they evolved in concert. We describe an evolutionary pathway in fungi where a new transcriptional circuit (a-specific gene repression by the homeodomain protein Matα2) evolved by coding changes in this ancient regulator, followed millions of years later by cis-regulatory sequence changes in the genes of its future regulon. By analyzing a group of species that has acquired the coding changes but not the cis-regulatory sites, we show that the coding changes became necessary for the regulator's deeply conserved function, thereby poising the regulator to jump-start formation of the new circuit.
Collapse
Affiliation(s)
- Candace S Britton
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94158, USA.,Tetrad Graduate Program, University of California, San Francisco, CA 94158, USA
| | - Trevor R Sorrells
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94158, USA.,Tetrad Graduate Program, University of California, San Francisco, CA 94158, USA
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94158, USA.
| |
Collapse
|
13
|
Trefflich S, Dalmolin RJS, Ortega JM, Castro MAA. Which came first, the transcriptional regulator or its target genes? An evolutionary perspective into the construction of eukaryotic regulons. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1863:194472. [PMID: 31825805 DOI: 10.1016/j.bbagrm.2019.194472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 11/06/2019] [Accepted: 11/30/2019] [Indexed: 01/06/2023]
Abstract
Eukaryotic regulons are regulatory units formed by a set of genes under the control of the same transcription factor (TF). Despite the functional plasticity, TFs are highly conserved and recognize the same DNA sequences in different organisms. One of the main factors that confer regulatory specificity is the distribution of the binding sites of the TFs along the genome, allowing the configuration of different transcriptional regulatory networks (TRNs) from the same regulator. A similar scenario occurs between tissues of the same organism, where a TRN can be rewired by epigenetic factors, modulating the accessibility of the TF to its binding sites. In this article we discuss concepts that can help to formulate testable hypotheses about the construction of regulons, exploring the presence and absence of the elements that form a TRN throughout the evolution of an ancestral lineage. This article is part of a Special Issue entitled: Transcriptional Profiles and Regulatory Gene Networks edited by Dr. Federico Manuel Giorgi and Dr. Shaun Mahony.
Collapse
Affiliation(s)
- Sheyla Trefflich
- Graduate Program in Bioinformatics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte 31270-901, Brazil; Bioinformatics and Systems Biology Laboratory, Federal University of Paraná, Curitiba 81520-260, Brazil
| | - Rodrigo J S Dalmolin
- Bioinformatics Multidisciplinary Environment, Federal University of Rio Grande do Norte, Natal 59078-400, Brazil
| | - José Miguel Ortega
- Graduate Program in Bioinformatics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte 31270-901, Brazil
| | - Mauro A A Castro
- Bioinformatics and Systems Biology Laboratory, Federal University of Paraná, Curitiba 81520-260, Brazil.
| |
Collapse
|
14
|
Miller SW, Movsesyan A, Zhang S, Fernández R, Posakony JW. Evolutionary emergence of Hairless as a novel component of the Notch signaling pathway. eLife 2019; 8:48115. [PMID: 31545167 PMCID: PMC6777938 DOI: 10.7554/elife.48115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 09/23/2019] [Indexed: 11/30/2022] Open
Abstract
Suppressor of Hairless [Su(H)], the transcription factor at the end of the Notch pathway in Drosophila, utilizes the Hairless protein to recruit two co-repressors, Groucho (Gro) and C-terminal Binding Protein (CtBP), indirectly. Hairless is present only in the Pancrustacea, raising the question of how Su(H) in other protostomes gains repressive function. We show that Su(H) from a wide array of arthropods, molluscs, and annelids includes motifs that directly bind Gro and CtBP; thus, direct co-repressor recruitment is ancestral in the protostomes. How did Hairless come to replace this ancestral paradigm? Our discovery of a protein (S-CAP) in Myriapods and Chelicerates that contains a motif similar to the Su(H)-binding domain in Hairless has revealed a likely evolutionary connection between Hairless and Metastasis-associated (MTA) protein, a component of the NuRD complex. Sequence comparison and widely conserved microsynteny suggest that S-CAP and Hairless arose from a tandem duplication of an ancestral MTA gene.
Collapse
Affiliation(s)
- Steven W Miller
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, United States
| | - Artem Movsesyan
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, United States
| | - Sui Zhang
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, United States
| | - Rosa Fernández
- Bioinformatics and Genomics Unit, Center for Genomic Regulation, Barcelona, Spain
| | - James W Posakony
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, United States
| |
Collapse
|
15
|
Devaux F, Thiébaut A. The regulation of iron homeostasis in the fungal human pathogen Candida glabrata. MICROBIOLOGY-SGM 2019; 165:1041-1060. [PMID: 31050635 DOI: 10.1099/mic.0.000807] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Iron is an essential element to most microorganisms, yet an excess of iron is toxic. Hence, living cells have to maintain a tight balance between iron uptake and iron consumption and storage. The control of intracellular iron concentrations is particularly challenging for pathogens because mammalian organisms have evolved sophisticated high-affinity systems to sequester iron from microbes and because iron availability fluctuates among the different host niches. In this review, we present the current understanding of iron homeostasis and its regulation in the fungal pathogen Candida glabrata. This yeast is an emerging pathogen which has become the second leading cause of candidemia, a life-threatening invasive mycosis. C. glabrata is relatively poorly studied compared to the closely related model yeast Saccharomyces cerevisiae or to the pathogenic yeast Candida albicans. Still, several research groups have started to identify the actors of C. glabrata iron homeostasis and its transcriptional and post-transcriptional regulation. These studies have revealed interesting particularities of C. glabrata and have shed new light on the evolution of fungal iron homeostasis.
Collapse
Affiliation(s)
- Frédéric Devaux
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, F-75005, Paris, France
| | - Antonin Thiébaut
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, F-75005, Paris, France
| |
Collapse
|
16
|
Bashor CJ, Patel N, Choubey S, Beyzavi A, Kondev J, Collins JJ, Khalil AS. Complex signal processing in synthetic gene circuits using cooperative regulatory assemblies. Science 2019; 364:593-597. [PMID: 31000590 DOI: 10.1126/science.aau8287] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 04/03/2019] [Indexed: 12/21/2022]
Abstract
Eukaryotic genes are regulated by multivalent transcription factor complexes. Through cooperative self-assembly, these complexes perform nonlinear regulatory operations involved in cellular decision-making and signal processing. In this study, we apply this design principle to synthetic networks, testing whether engineered cooperative assemblies can program nonlinear gene circuit behavior in yeast. Using a model-guided approach, we show that specifying the strength and number of assembly subunits enables predictive tuning between linear and nonlinear regulatory responses for single- and multi-input circuits. We demonstrate that assemblies can be adjusted to control circuit dynamics. We harness this capability to engineer circuits that perform dynamic filtering, enabling frequency-dependent decoding in cell populations. Programmable cooperative assembly provides a versatile way to tune the nonlinearity of network connections, markedly expanding the engineerable behaviors available to synthetic circuits.
Collapse
Affiliation(s)
- Caleb J Bashor
- Department of Bioengineering, Rice University, Houston, TX 77030, USA
| | - Nikit Patel
- Department of Biomedical Engineering and Biological Design Center, Boston University, Boston, MA 02215, USA
| | - Sandeep Choubey
- Department of Physics, Brandeis University, Waltham, MA 02453, USA
| | - Ali Beyzavi
- Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA
| | - Jané Kondev
- Department of Physics, Brandeis University, Waltham, MA 02453, USA
| | - James J Collins
- Institute for Medical Engineering and Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Ahmad S Khalil
- Department of Biomedical Engineering and Biological Design Center, Boston University, Boston, MA 02215, USA. .,Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| |
Collapse
|
17
|
Evolutionary Transition of GAL Regulatory Circuit from Generalist to Specialist Function in Ascomycetes. Trends Microbiol 2019; 26:692-702. [PMID: 29395731 DOI: 10.1016/j.tim.2017.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 11/23/2022]
Abstract
The Gal4 transcription factor (TF) controls gene expression by binding the DNA sequence motif CGG(N11)CCG. Well studied versions regulate metabolism of glucose in Candida albicans and galactose in Saccharomyces cerevisiae. Gal4 is also found within Aspergillus species and shows a wide range of potential binding targets. Members of the CTG clade that reassigned CUG codons from leucine to serine lack the Gal80 binding domain of Gal4, and they use the TF to regulate only glycolytic genes. In this clade, the galactose catabolic pathway (also known as the Leloir pathway) genes are regulated by Rtg1/Rtg3. In the WGD species, the complete Gal4/Gal80 module is limited to regulation of the Leloir pathway, while glycolysis is controlled by Gcr1/Gcr2. This shows a switch of Gal4 from a generalist to a specialist within the ascomycetes, and the split of glucose and galactose metabolism into distinct regulatory circuits.
Collapse
|
18
|
Bizzarri M, Cassanelli S, Bartolini L, Pryszcz LP, Dušková M, Sychrová H, Solieri L. Interplay of Chimeric Mating-Type Loci Impairs Fertility Rescue and Accounts for Intra-Strain Variability in Zygosaccharomyces rouxii Interspecies Hybrid ATCC42981. Front Genet 2019; 10:137. [PMID: 30881382 PMCID: PMC6405483 DOI: 10.3389/fgene.2019.00137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 02/11/2019] [Indexed: 11/13/2022] Open
Abstract
The pre-whole genome duplication (WGD) Zygosaccharomyces clade comprises several allodiploid strain/species with industrially interesting traits. The salt-tolerant yeast ATCC42981 is a sterile and allodiploid strain which contains two subgenomes, one of them resembling the haploid parental species Z. rouxii. Recently, different mating-type-like (MTL) loci repertoires were reported for ATCC42981 and the Japanese strain JCM22060, which are considered two stocks of the same strain. MTL reconstruction by direct sequencing approach is challenging due to gene redundancy, structure complexities, and allodiploid nature of ATCC42981. Here, DBG2OLC and MaSuRCA hybrid de novo assemblies of ONT and Illumina reads were combined with in vitro long PCR to definitively solve these incongruences. ATCC42981 exhibits several chimeric MTL loci resulting from reciprocal translocation between parental haplotypes and retains two MATa/MATα expression loci, in contrast to MATα in JCM22060. Consistently to these reconstructions, JCM22060, but not ATCC42981, undergoes mating and meiosis. To ascertain whether the damage of one allele at the MAT locus regains the complete sexual cycle in ATCC42981, we removed the MATα expressed locus by gene deletion. The resulting MATa/- hemizygous mutants did not show any evidence of sporulation, as well as of self- and out-crossing fertility, probably because incomplete silencing at the chimeric HMLα cassette masks the loss of heterozygosity at the MAT locus. We also found that MATα deletion switched off a2 transcription, an activator of a-specific genes in pre-WGD species. These findings suggest that regulatory scheme of cell identity needs to be further investigated in Z. rouxii protoploid yeast.
Collapse
Affiliation(s)
- Melissa Bizzarri
- Department of Life Sciences, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| | - Stefano Cassanelli
- Department of Life Sciences, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| | - Laura Bartolini
- Department of Life Sciences, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| | - Leszek P. Pryszcz
- Laboratory of Zebrafish Developmental Genomics, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Michala Dušková
- Department of Membrane Transport, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Hana Sychrová
- Department of Membrane Transport, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Lisa Solieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| |
Collapse
|
19
|
Brown AJ, Gow NA, Warris A, Brown GD. Memory in Fungal Pathogens Promotes Immune Evasion, Colonisation, and Infection. Trends Microbiol 2019; 27:219-230. [DOI: 10.1016/j.tim.2018.11.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/19/2018] [Accepted: 11/01/2018] [Indexed: 12/20/2022]
|
20
|
Huang JH, Kwan RSY, Tsai ZTY, Lin TC, Tsai HK. Borders of Cis-Regulatory DNA Sequences Preferentially Harbor the Divergent Transcription Factor Binding Motifs in the Human Genome. Front Genet 2018; 9:571. [PMID: 30524473 PMCID: PMC6261980 DOI: 10.3389/fgene.2018.00571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/06/2018] [Indexed: 11/17/2022] Open
Abstract
Changes in cis-regulatory DNA sequences and transcription factor (TF) repertoires provide major sources of phenotypic diversity that shape the evolution of gene regulation in eukaryotes. The DNA-binding specificities of TFs may be diversified or produce new variants in different eukaryotic species. However, it is currently unclear how various levels of divergence in TF DNA-binding specificities or motifs became introduced into the cis-regulatory DNA regions of the genome over evolutionary time. Here, we first estimated the evolutionary divergence levels of TF binding motifs and quantified their occurrence at DNase I-hypersensitive sites. Results from our in silico motif scan and experimentally derived chromatin immunoprecipitation (TF-ChIP) show that the divergent motifs tend to be introduced in the edges of cis-regulatory regions, which is probably accompanied by the expansion of the accessible core of promoter-associated regulatory elements during evolution. We also find that the genes neighboring the expanded cis-regulatory regions with the most divergent motifs are associated with functions like development and morphogenesis. Accordingly, we propose that the accumulation of divergent motifs in the edges of cis-regulatory regions provides a functional mechanism for the evolution of divergent regulatory circuits.
Collapse
Affiliation(s)
- Jia-Hsin Huang
- Institute of Information Science, Academia Sinica, Nankang, Taipei, Taiwan
| | | | - Zing Tsung-Yeh Tsai
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, United States
| | - Tzu-Chieh Lin
- Institute of Information Science, Academia Sinica, Nankang, Taipei, Taiwan
| | - Huai-Kuang Tsai
- Institute of Information Science, Academia Sinica, Nankang, Taipei, Taiwan
| |
Collapse
|
21
|
Structural modules of the stress-induced protein HflX: an outlook on its evolution and biological role. Curr Genet 2018; 65:363-370. [PMID: 30448945 DOI: 10.1007/s00294-018-0905-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/05/2018] [Accepted: 11/13/2018] [Indexed: 12/23/2022]
Abstract
Multifunctional proteins often show modular structures. A functional domain and the structural modules within the domain show evolutionary conservation of their spatial arrangement since that gives the protein its functionality. However, the question remains as to how members of different domains of life (Archaea, Bacteria, Eukarya), polish and perfect these modules within conserved multidomain proteins, to tailor functional proteins according to their specific requirements. In the quest for plausible answers to this question, we studied the bacterial protein HflX. HflX is a universally conserved member of the Obg-GTPase superfamily but its functional role in Archaea and Eukarya is barely known. It is a multidomain protein and possesses, in addition to its conserved GTPase domain, an ATP-binding N-terminal domain. It is involved in heat stress response in Escherichia coli and our laboratory recently identified an ATP-dependent RNA helicase activity of E. coli HflX, which is likely instrumental in rescuing ribosomes during heat stress. Because perception and response to stress is expected to be different in different life forms, the question is whether this activity is preserved in higher organisms or not. Thus, we explored the evolution pattern of different structural modules of HflX, with particular emphasis on the ATP-binding domain, to understand plausible biological role of HflX in other forms of life. Our analyses indicate that, while the evolutionary pattern of the GTPase domain follows a conserved phylogeny, conservation of the ATP-binding domain shows a complicated pattern. The limited analysis described here hints towards possible evolutionary adaptations and modifications of the domain, something which needs to be investigated in more depth in homologs from other life forms. Deciphering how nature 'tweaks' such modules, both structurally and functionally, may help in understanding the evolution of such proteins, and, on a large-scale, of stress-related proteins in general as well.
Collapse
|
22
|
Liu Q, Onal P, Datta RR, Rogers JM, Schmidt-Ott U, Bulyk ML, Small S, Thornton JW. Ancient mechanisms for the evolution of the bicoid homeodomain's function in fly development. eLife 2018; 7:e34594. [PMID: 30298815 PMCID: PMC6177261 DOI: 10.7554/elife.34594] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/28/2018] [Indexed: 12/14/2022] Open
Abstract
The ancient mechanisms that caused developmental gene regulatory networks to diversify among distantly related taxa are not well understood. Here we use ancestral protein reconstruction, biochemical experiments, and developmental assays of transgenic animals carrying reconstructed ancestral genes to investigate how the transcription factor Bicoid (Bcd) evolved its central role in anterior-posterior patterning in flies. We show that most of Bcd's derived functions are attributable to evolutionary changes within its homeodomain (HD) during a phylogenetic interval >140 million years ago. A single substitution from this period (Q50K) accounts almost entirely for the evolution of Bcd's derived DNA specificity in vitro. In transgenic embryos expressing the reconstructed ancestral HD, however, Q50K confers activation of only a few of Bcd's transcriptional targets and yields a very partial rescue of anterior development. Adding a second historical substitution (M54R) confers regulation of additional Bcd targets and further rescues anterior development. These results indicate that two epistatically interacting mutations played a major role in the evolution of Bcd's controlling regulatory role in early development. They also show how ancestral sequence reconstruction can be combined with in vivo characterization of transgenic animals to illuminate the historical mechanisms of developmental evolution.
Collapse
Affiliation(s)
- Qinwen Liu
- Department of Ecology and EvolutionUniversity of ChicagoChicagoUnited States
| | - Pinar Onal
- Department of BiologyNew York UniversityNew YorkUnited States
| | - Rhea R Datta
- Department of BiologyNew York UniversityNew YorkUnited States
| | - Julia M Rogers
- Committee on Higher Degrees in BiophysicsHarvard UniversityCambridgeUnited States
- Division of Genetics, Department of MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBostonUnited States
| | - Urs Schmidt-Ott
- Department of Organismal Biology and AnatomyUniversity of ChicagoChicagoUnited States
| | - Martha L Bulyk
- Committee on Higher Degrees in BiophysicsHarvard UniversityCambridgeUnited States
- Division of Genetics, Department of MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBostonUnited States
- Department of PathologyBrigham and Women’s Hospital and Harvard Medical SchoolBostonUnited States
| | - Stephen Small
- Department of BiologyNew York UniversityNew YorkUnited States
| | - Joseph W Thornton
- Department of Ecology and EvolutionUniversity of ChicagoChicagoUnited States
- Department of Human GeneticsUniversity of ChicagoChicagoUnited States
| |
Collapse
|
23
|
Sorrells TR, Johnson AN, Howard CJ, Britton CS, Fowler KR, Feigerle JT, Weil PA, Johnson AD. Intrinsic cooperativity potentiates parallel cis-regulatory evolution. eLife 2018; 7:37563. [PMID: 30198843 PMCID: PMC6173580 DOI: 10.7554/elife.37563] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 09/09/2018] [Indexed: 12/27/2022] Open
Abstract
Convergent evolutionary events in independent lineages provide an opportunity to understand why evolution favors certain outcomes over others. We studied such a case where a large set of genes-those coding for the ribosomal proteins-gained cis-regulatory sequences for a particular transcription regulator (Mcm1) in independent fungal lineages. We present evidence that these gains occurred because Mcm1 shares a mechanism of transcriptional activation with an ancestral regulator of the ribosomal protein genes, Rap1. Specifically, we show that Mcm1 and Rap1 have the inherent ability to cooperatively activate transcription through contacts with the general transcription factor TFIID. Because the two regulatory proteins share a common interaction partner, the presence of one ancestral cis-regulatory sequence can 'channel' random mutations into functional sites for the second regulator. At a genomic scale, this type of intrinsic cooperativity can account for a pattern of parallel evolution involving the fixation of hundreds of substitutions.
Collapse
Affiliation(s)
- Trevor R Sorrells
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Amanda N Johnson
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Conor J Howard
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Candace S Britton
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Kyle R Fowler
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Jordan T Feigerle
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - P Anthony Weil
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Alexander D Johnson
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| |
Collapse
|
24
|
Rogers JM, Bulyk ML. Diversification of transcription factor-DNA interactions and the evolution of gene regulatory networks. WILEY INTERDISCIPLINARY REVIEWS. SYSTEMS BIOLOGY AND MEDICINE 2018; 10:e1423. [PMID: 29694718 PMCID: PMC6202284 DOI: 10.1002/wsbm.1423] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 02/23/2018] [Accepted: 03/11/2018] [Indexed: 01/17/2023]
Abstract
Sequence-specific transcription factors (TFs) bind short DNA sequences in the genome to regulate the expression of target genes. In the last decade, numerous technical advances have enabled the determination of the DNA-binding specificities of many of these factors. Large-scale screens of many TFs enabled the creation of databases of TF DNA-binding specificities, typically represented as position weight matrices (PWMs). Although great progress has been made in determining and predicting binding specificities systematically, there are still many surprises to be found when studying a particular TF's interactions with DNA in detail. Paralogous TFs' binding specificities can differ in subtle ways, in a manner that is not immediately apparent from looking at their PWMs. These differences affect gene regulatory outputs and enable TFs to rewire transcriptional networks over evolutionary time. This review discusses recent observations made in the study of TF-DNA interactions that highlight the importance of continued in-depth analysis of TF-DNA interactions and their inherent complexity. This article is categorized under: Biological Mechanisms > Regulatory Biology.
Collapse
Affiliation(s)
- Julia M. Rogers
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, 02115, USA,Committee on Higher Degrees in Biophysics, Harvard University, Cambridge, MA, 02138, USA
| | - Martha L. Bulyk
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, 02115, USA,Committee on Higher Degrees in Biophysics, Harvard University, Cambridge, MA, 02138, USA,Department of Pathology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, 02115, USA
| |
Collapse
|
25
|
Bartlett ME. Changing MADS-Box Transcription Factor Protein-Protein Interactions as a Mechanism for Generating Floral Morphological Diversity. Integr Comp Biol 2018; 57:1312-1321. [PMID: 28992040 DOI: 10.1093/icb/icx067] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Flowers display fantastic morphological diversity. Despite extreme variability in form, floral organ identity is specified by a core set of deeply conserved proteins-the floral MADS-box transcription factors. This indicates that while core gene function has been maintained, MADS-box transcription factors have evolved to regulate different downstream genes. Thus, the evolution of gene regulation downstream of the MADS-box transcription factors is likely central to the evolution of floral form. Gene regulation is determined by the combination of transcriptional regulators present at a particular cis-regulatory element at a particular time. Therefore, the interactions between transcription factors can be of profound importance in determining patterns of gene regulation. Here, after a short primer on flowers and floral morphology, I discuss the centrality of protein-protein interactions to MADS-box transcription factor function, and review the evidence that the evolution of MADS-box protein-protein interactions is a key driver in the evolution of gene regulation downstream of the MADS-box genes.
Collapse
Affiliation(s)
- Madelaine E Bartlett
- Biology Department, University of Massachusetts Amherst, 611 North Pleasant St., 374 Morrill 4?S, Amherst, MA 01003, USA
| |
Collapse
|
26
|
Tenno M, Kojo S, Lawir DF, Hess I, Shiroguchi K, Ebihara T, Endo TA, Muroi S, Satoh R, Kawamoto H, Boehm T, Taniuchi I. Cbfβ2 controls differentiation of and confers homing capacity to prethymic progenitors. J Exp Med 2018; 215:595-610. [PMID: 29343500 PMCID: PMC5789415 DOI: 10.1084/jem.20171221] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/28/2017] [Accepted: 12/13/2017] [Indexed: 01/05/2023] Open
Abstract
Tenno et al. show that an evolutionarily conserved alternative splicing event in the Cbfb gene generates Cbfβ2, which forms a functionally distinct transcription factor complex underlying the differentiation of extrathymic T cell progenitors, including induction of the principal thymus-homing receptor, Ccr9. Multipotent hematopoietic progenitors must acquire thymus-homing capacity to initiate T lymphocyte development. Despite its importance, the transcriptional program underlying this process remains elusive. Cbfβ forms transcription factor complexes with Runx proteins, and here we show that Cbfβ2, encoded by an RNA splice variant of the Cbfb gene, is essential for extrathymic differentiation of T cell progenitors. Furthermore, Cbfβ2 endows extrathymic progenitors with thymus-homing capacity by inducing expression of the principal thymus-homing receptor, Ccr9. This occurs via direct binding of Cbfβ2 to cell type–specific enhancers, as is observed in Rorγt induction during differentiation of lymphoid tissue inducer cells by activation of an intronic enhancer. As in mice, an alternative splicing event in zebrafish generates a Cbfβ2-specific mRNA, important for ccr9 expression. Thus, despite phylogenetically and ontogenetically variable sites of origin of T cell progenitors, their robust thymus-homing capacity is ensured by an evolutionarily conserved mechanism emerging from functional diversification of Runx transcription factor complexes by acquisition of a novel splice variant.
Collapse
Affiliation(s)
- Mari Tenno
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan
| | - Satoshi Kojo
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan
| | - Divine-Fondzenyuy Lawir
- Department of Developmental Immunology, Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Isabell Hess
- Department of Developmental Immunology, Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Katsuyuki Shiroguchi
- Laboratory for Immunogenetics, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan.,Laboratory for Integrative Omics, RIKEN Quantitative Biology Center, Osaka, Japan.,Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Saitama, Japan
| | - Takashi Ebihara
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan
| | - Takaho A Endo
- Laboratory for Integrative Genomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan
| | - Sawako Muroi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan
| | - Rumi Satoh
- Laboratory for Lymphocyte Development, RIKEN Center for Allergy and Immunology, Yokohama, Japan
| | - Hiroshi Kawamoto
- Laboratory for Lymphocyte Development, RIKEN Center for Allergy and Immunology, Yokohama, Japan
| | - Thomas Boehm
- Department of Developmental Immunology, Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan
| |
Collapse
|
27
|
Creation of Stable Heterothallic Strains of Komagataella phaffii Enables Dissection of Mating Gene Regulation. Mol Cell Biol 2017; 38:MCB.00398-17. [PMID: 29061733 PMCID: PMC5748462 DOI: 10.1128/mcb.00398-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 10/16/2017] [Indexed: 11/20/2022] Open
Abstract
The methylotrophic yeast Komagataella phaffii (Pichia pastoris) is homothallic and has been reported to switch mating type by an ancient inversion mechanism. Two mating-type (MAT) loci include homologs of the MATa and MATα transcription factor genes, with the expression from one locus downregulated by telomere position effects. However, not much is known about mating gene regulation, since the mixture of mating types complicates detailed investigations. In this study, we developed K. phaffii strains with stable mating types by deletion of the inverted-repeat region required for mating-type switching. These heterothallic strains retain their ability to mate with cells of the opposite mating type and were used to further elucidate mating gene regulation. Functional analysis of MAT mutant strains revealed the essential role of MATa2 and MATα1 in diploid cell formation. Disruption of MATa1 or MATα2 did not affect mating; however, in diploid cells, both genes are required for sporulation and the repression of shmoo formation. The heterothallic strains generated in this study allowed the first detailed characterization of mating gene regulation in K. phaffii They will be a valuable tool for further studies investigating cell-type-specific behavior and will enable in-depth genetic analyses and strain hybridization in this industrially relevant yeast species.
Collapse
|
28
|
Dalal CK, Johnson AD. How transcription circuits explore alternative architectures while maintaining overall circuit output. Genes Dev 2017; 31:1397-1405. [PMID: 28860157 PMCID: PMC5588923 DOI: 10.1101/gad.303362.117] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
This review by Dalal and Johnson focuses on the evolutionary rewiring of transcription regulators and the conservation of patterns of gene expression. They describe how preservation of gene expression patterns in the wake of extensive rewiring is a general feature of transcription circuit evolution. Transcription regulators bind to cis-regulatory sequences and thereby control the expression of target genes. While transcription regulators and the target genes that they regulate are often deeply conserved across species, the connections between the two change extensively over evolutionary timescales. In this review, we discuss case studies where, despite this extensive evolutionary rewiring, the resulting patterns of gene expression are preserved. We also discuss in silico models that reach the same general conclusions and provide additional insights into how this process occurs. Together, these approaches make a strong case that the preservation of gene expression patterns in the wake of extensive rewiring is a general feature of transcription circuit evolution.
Collapse
Affiliation(s)
- Chiraj K Dalal
- Department of Microbiology and Immunology, University of California at San Francisco, San Francisco, California 94158, USA
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California at San Francisco, San Francisco, California 94158, USA.,Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| |
Collapse
|
29
|
The rewiring of transcription circuits in evolution. Curr Opin Genet Dev 2017; 47:121-127. [PMID: 29120735 DOI: 10.1016/j.gde.2017.09.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 09/13/2017] [Accepted: 09/14/2017] [Indexed: 12/24/2022]
Abstract
The binding of transcription regulators to cis-regulatory sequences is a key step through which all cells regulate expression of their genes. Due to gains and losses of cis-regulatory sequences and changes in the transcription regulators themselves, the binding connections between regulators and their target genes rapidly change over evolutionary time and constitute a major source of biological novelty. This review covers recent work, carried out in a wide range of species, that addresses the overall extent of these evolutionary changes, their consequences, and some of the molecular mechanisms that lie behind them.
Collapse
|
30
|
Wasserstrom L, Dünkler A, Walther A, Wendland J. The APSES protein Sok2 is a positive regulator of sporulation in Ashbya gossypii. Mol Microbiol 2017; 106:949-960. [PMID: 28985003 DOI: 10.1111/mmi.13859] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2017] [Indexed: 01/26/2023]
Abstract
Ashbya gossypii is a homothallic, flavinogenic, filamentous ascomycete that starts overproduction of riboflavin and fragments its mycelium quantitatively into spore producing sporangia at the end of a growth phase. Mating is not required for sporulation and the standard homothallic laboratory strain is a MATa strain. Here we show that ectopic expression of Saccharomyces cerevisiae MATα2 in A. gossypii completely suppresses sporulation, inhibits riboflavin overproduction and downregulates among others AgSOK2. AgSok2 belongs to a fungal-specific group of (APSES) transcription factors. Deletion of AgSOK2 strongly reduces riboflavin production and blocks sporulation. The initiator of meiosis, AgIME1, is a transcription factor essential for sporulation. We characterized the AgIME1 promoter region required for complementation of the Agime1 mutant. Reporter assays with AgIME1 promoter fragments fused to lacZ showed that AgSok2 does not control AgIME1 transcription. However, global transcriptome analysis identified two other essential regulators of sporulation, AgIME2 and AgNDT80, as potential targets of AgSok2. Our data suggest that sporulation and riboflavin production in A. gossypii are under mating type locus and nutritional control. Sok2, a target of the cAMP/protein kinase A pathway, serves as a central positive regulator to promote sporulation. This contrasts Saccharomyces cerevisiae where Sok2 is a repressor of IME1 transcription.
Collapse
Affiliation(s)
- Lisa Wasserstrom
- Carlsberg Laboratory, Yeast & Fermentation, DK-1799 Copenhagen V, Denmark
| | - Alexander Dünkler
- Carlsberg Laboratory, Yeast & Fermentation, DK-1799 Copenhagen V, Denmark
| | - Andrea Walther
- Carlsberg Laboratory, Yeast & Fermentation, DK-1799 Copenhagen V, Denmark
| | - Jürgen Wendland
- Carlsberg Laboratory, Yeast & Fermentation, DK-1799 Copenhagen V, Denmark.,Vrije Universiteit Brussel, Department of Bioengineering Sciences Research Group of Microbiology, Functional Yeast Genomics, BE-1050 Brussels, Belgium
| |
Collapse
|
31
|
Affiliation(s)
- Kenneth H. Wolfe
- School of Medicine, Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Geraldine Butler
- School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Ireland
| |
Collapse
|
32
|
Abstract
This article provides an overview of sexual reproduction in the ascomycetes, a phylum of fungi that is named after the specialized sacs or "asci" that hold the sexual spores. They have therefore also been referred to as the Sac Fungi due to these characteristic structures that typically contain four to eight ascospores. Ascomycetes are morphologically diverse and include single-celled yeasts, filamentous fungi, and more complex cup fungi. The sexual cycles of many species, including those of the model yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe and the filamentous saprobes Neurospora crassa, Aspergillus nidulans, and Podospora anserina, have been examined in depth. In addition, sexual or parasexual cycles have been uncovered in important human pathogens such as Candida albicans and Aspergillus fumigatus, as well as in plant pathogens such as Fusarium graminearum and Cochliobolus heterostrophus. We summarize what is known about sexual fecundity in ascomycetes, examine how structural changes at the mating-type locus dictate sexual behavior, and discuss recent studies that reveal that pheromone signaling pathways can be repurposed to serve cellular roles unrelated to sex.
Collapse
|
33
|
Abstract
Cell differentiation in yeast species is controlled by a reversible, programmed DNA-rearrangement process called mating-type switching. Switching is achieved by two functionally similar but structurally distinct processes in the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe. In both species, haploid cells possess one active and two silent copies of the mating-type locus (a three-cassette structure), the active locus is cleaved, and synthesis-dependent strand annealing is used to replace it with a copy of a silent locus encoding the opposite mating-type information. Each species has its own set of components responsible for regulating these processes. In this review, we summarize knowledge about the function and evolution of mating-type switching components in these species, including mechanisms of heterochromatin formation, MAT locus cleavage, donor bias, lineage tracking, and environmental regulation of switching. We compare switching in these well-studied species to others such as Kluyveromyces lactis and the methylotrophic yeasts Ogataea polymorpha and Komagataella phaffii. We focus on some key questions: Which cells switch mating type? What molecular apparatus is required for switching? Where did it come from? And what is the evolutionary purpose of switching?
Collapse
|
34
|
Gordon JL, Gallone B, Maere S, Verstrepen KJ. Evolutionary Context Improves Regulatory Network Predictions. Cell Syst 2017; 4:478-479. [PMID: 28544878 DOI: 10.1016/j.cels.2017.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A novel algorithm harnesses phylogenetic information and facilitates a better understanding of the evolutionary divergence of gene regulation between species.
Collapse
Affiliation(s)
- Jonathan L Gordon
- VIB Center for Microbiology and Laboratory for Genetics and Genomics, Department M2S, KU Leuven, Bio-Incubator, Gaston Geenslaan 1, 3001 Leuven, Belgium
| | - Brigida Gallone
- VIB Center for Microbiology and Laboratory for Genetics and Genomics, Department M2S, KU Leuven, Bio-Incubator, Gaston Geenslaan 1, 3001 Leuven, Belgium; VIB Center for Plant Systems Biology and Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Steven Maere
- VIB Center for Plant Systems Biology and Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Kevin J Verstrepen
- VIB Center for Microbiology and Laboratory for Genetics and Genomics, Department M2S, KU Leuven, Bio-Incubator, Gaston Geenslaan 1, 3001 Leuven, Belgium.
| |
Collapse
|
35
|
Ortiz-Merino RA, Kuanyshev N, Braun-Galleani S, Byrne KP, Porro D, Branduardi P, Wolfe KH. Evolutionary restoration of fertility in an interspecies hybrid yeast, by whole-genome duplication after a failed mating-type switch. PLoS Biol 2017; 15:e2002128. [PMID: 28510588 PMCID: PMC5433688 DOI: 10.1371/journal.pbio.2002128] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 04/13/2017] [Indexed: 11/30/2022] Open
Abstract
Many interspecies hybrids have been discovered in yeasts, but most of these hybrids are asexual and can replicate only mitotically. Whole-genome duplication has been proposed as a mechanism by which interspecies hybrids can regain fertility, restoring their ability to perform meiosis and sporulate. Here, we show that this process occurred naturally during the evolution of Zygosaccharomyces parabailii, an interspecies hybrid that was formed by mating between 2 parents that differed by 7% in genome sequence and by many interchromosomal rearrangements. Surprisingly, Z. parabailii has a full sexual cycle and is genetically haploid. It goes through mating-type switching and autodiploidization, followed by immediate sporulation. We identified the key evolutionary event that enabled Z. parabailii to regain fertility, which was breakage of 1 of the 2 homeologous copies of the mating-type (MAT) locus in the hybrid, resulting in a chromosomal rearrangement and irreparable damage to 1 MAT locus. This rearrangement was caused by HO endonuclease, which normally functions in mating-type switching. With 1 copy of MAT inactivated, the interspecies hybrid now behaves as a haploid. Our results provide the first demonstration that MAT locus damage is a naturally occurring evolutionary mechanism for whole-genome duplication and restoration of fertility to interspecies hybrids. The events that occurred in Z. parabailii strongly resemble those postulated to have caused ancient whole-genome duplication in an ancestor of Saccharomyces cerevisiae. It has recently been proposed that the whole-genome duplication (WGD) event that occurred during evolution of an ancestor of the yeast S. cerevisiae was the result of a hybridization between 2 parental yeast species that were significantly divergent in DNA sequence, followed by a doubling of the genome content to restore the hybrid’s ability to make viable spores. However, the molecular details of how genome doubling could occur in a hybrid were unclear because most known interspecies hybrid yeasts have no sexual cycle. We show here that Z. parabailii provides an almost exact precedent for the steps proposed to have occurred during the S. cerevisiae WGD. Two divergent haploid parental species, each with 8 chromosomes, mated to form a hybrid that was initially sterile but regained fertility when 1 copy of its mating-type locus became damaged by the mating-type switching apparatus. As a result of this damage, the Z. parabailii life cycle now consists of a 16-chromosome haploid phase and a transient 32-chromosome diploid phase. Each pair of homeologous genes behaves as 2 independent Mendelian loci during meiosis.
Collapse
Affiliation(s)
- Raúl A. Ortiz-Merino
- UCD Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
| | - Nurzhan Kuanyshev
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy
| | | | - Kevin P. Byrne
- UCD Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
| | - Danilo Porro
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy
| | - Paola Branduardi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy
| | - Kenneth H. Wolfe
- UCD Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
- * E-mail:
| |
Collapse
|
36
|
He BZ, Zhou X, O'Shea EK. Evolution of reduced co-activator dependence led to target expansion of a starvation response pathway. eLife 2017; 6:25157. [PMID: 28485712 PMCID: PMC5446240 DOI: 10.7554/elife.25157] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 04/29/2017] [Indexed: 01/23/2023] Open
Abstract
Although combinatorial regulation is a common feature in gene regulatory networks, how it evolves and affects network structure and function is not well understood. In S. cerevisiae, the phosphate starvation (PHO) responsive transcription factors Pho4 and Pho2 are required for gene induction and survival during phosphate starvation. In the related human commensal C. glabrata, Pho4 is required but Pho2 is dispensable for survival in phosphate starvation and is only partially required for inducing PHO genes. Phylogenetic survey suggests that reduced dependence on Pho2 evolved in C. glabrata and closely related species. In S. cerevisiae, less Pho2-dependent Pho4 orthologs induce more genes. In C. glabrata, its Pho4 binds to more locations and induces three times as many genes as Pho4 in S. cerevisiae does. Our work shows how evolution of combinatorial regulation allows for rapid expansion of a gene regulatory network’s targets, possibly extending its physiological functions. The diversity of life on Earth has intrigued generations of scientists and nature lovers alike. Research over recent decades has revealed that much of the diversity we can see did not require the invention of new genes. Instead, living forms diversified mostly by using old genes in new ways – for example, by changing when or where an existing gene became active. This kind of change is referred to as “regulatory evolution”. A class of proteins called transcription factors are hot spots in regulatory evolution. These proteins recognize specific sequences of DNA to control the activity of other genes, and so represent the “readers” of the genetic information. Small changes to how a transcription factor is regulated, or the genes it targets, can lead to dramatic changes in an organism. Before we can understand how life on Earth evolved to be so diverse, scientists must first answer how transcription factors evolve and what consequences this has on their target genes. So far, most studies of regulatory evolution have focused on networks of transcription factors and genes that control how an organism develops. He et al. have now studied a regulatory network that is behind a different process, namely how an organism responds to stress or starvation. These two types of regulatory networks are structured differently and work in different ways. These differences made He et al. wonder if the networks evolved differently too. The chemical phosphate is an essential nutrient for all living things, and He et al. compared how two different species of yeast responded to a lack of phosphate. The key difference was how much a major transcription factor known as Pho4 depended on a so-called co-activator protein named Pho2 to carry out its role. Baker’s yeast (Saccharomyces cerevisiae), which is commonly used in laboratory experiments, requires both Pho4 and Pho2 to activate about 20 genes when inorganic phosphate is not available in its environment. However, in a related yeast species called Candida glabrata, Pho4 has evolved to depend less on Pho2. He et al. went on to show that, as well as being less dependent on Pho2, Pho4 in C. glabrata activates more than three times as many genes as Pho4 in S. cerevisiae does in the absence of phosphate. These additional gene targets for Pho4 in C. glabrata are predicted to extend the network’s activities, and allow it to regulate new process including the yeast’s responses to other types of stress and the building of the yeast’s cell wall. Together these findings show a new way that regulatory networks can evolve, that is, by reducing its dependence on the co-activator, a transcription factor can expand the number of genes it targets. This has not been seen for regulatory networks related to development, suggesting that different networks can indeed evolve in different ways. Lastly, because disease-causing microbes are often stressed inside their hosts and C. glabrata sometimes infects humans, understanding how this yeast’s response to stress has evolved may lead to new ways to prevent and treat this infection.
Collapse
Affiliation(s)
- Bin Z He
- Faculty of Arts and Sciences Center for Systems Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States
| | - Xu Zhou
- Faculty of Arts and Sciences Center for Systems Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States
| | - Erin K O'Shea
- Faculty of Arts and Sciences Center for Systems Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, United States
| |
Collapse
|
37
|
Chow EWL, Clancey SA, Billmyre RB, Averette AF, Granek JA, Mieczkowski P, Cardenas ME, Heitman J. Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans. PLoS Genet 2017; 13:e1006667. [PMID: 28376087 PMCID: PMC5380312 DOI: 10.1371/journal.pgen.1006667] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 03/01/2017] [Indexed: 12/02/2022] Open
Abstract
Calcineurin is a highly conserved Ca2+/calmodulin-dependent serine/threonine-specific protein phosphatase that orchestrates cellular Ca2+ signaling responses. In Cryptococcus neoformans, calcineurin is activated by multiple stresses including high temperature, and is essential for stress adaptation and virulence. The transcription factor Crz1 is a major calcineurin effector in Saccharomyces cerevisiae and other fungi. Calcineurin dephosphorylates Crz1, thereby enabling Crz1 nuclear translocation and transcription of target genes. Here we show that loss of Crz1 confers phenotypes intermediate between wild-type and calcineurin mutants, and demonstrate that deletion of the calcineurin docking domain results in the inability of Crz1 to translocate into the nucleus under thermal stress. RNA-sequencing revealed 102 genes that are regulated in a calcineurin-Crz1-dependent manner at 37°C. The majority of genes were down-regulated in cna1Δ and crz1Δ mutants, indicating these genes are normally activated by the calcineurin-Crz1 pathway at high temperature. About 58% of calcineurin-Crz1 target genes have unknown functions, while genes with known or predicted functions are involved in cell wall remodeling, calcium transport, and pheromone production. We identified three calcineurin-dependent response element motifs within the promoter regions of calcineurin-Crz1 target genes, and show that Crz1 binding to target gene promoters is increased upon thermal stress in a calcineurin-dependent fashion. Additionally, we found a large set of genes independently regulated by calcineurin, and Crz1 regulates 59 genes independently of calcineurin. Given the intermediate crz1Δ mutant phenotype, and our recent evidence for a calcineurin regulatory network impacting mRNA in P-bodies and stress granules independently of Crz1, calcineurin likely acts on factors beyond Crz1 that govern mRNA expression/stability to operate a branched transcriptional/post-transcriptional stress response network necessary for fungal virulence. Taken together, our findings reveal the core calcineurin-Crz1 stress response cascade is maintained from ascomycetes to a pathogenic basidiomycete fungus, but its output in C. neoformans appears to be adapted to promote fungal virulence. The ubquitiously conserved serine/threonine-specific protein phosphatase calcineurin is crucial for virulence of several opportunistic human fungal pathogens including Candida albicans, Aspergillus fumigatus, and Cryptococcus neoformans. We show that Crz1 acts downstream of calcineurin, to 1) govern expression of genes involved in cell wall integrity, and calcium and small molecule transport, and 2) contribute to stress survival and virulence of C. neoformans. Our studies reveal that calcineurin also controls mRNA expression levels of other genes independently of Crz1. We propose that calcineurin operates in a branched signal transduction cascade controlling targets at both the transcriptional and post-transcriptional levels.
Collapse
Affiliation(s)
- Eve W. L. Chow
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Shelly A. Clancey
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - R. Blake Billmyre
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Anna Floyd Averette
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Joshua A. Granek
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina, United States of America
- Duke Center for the Genomics of Microbial Systems, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Piotr Mieczkowski
- High-Throughput Sequencing Facility, School of Medicine, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Maria E. Cardenas
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
38
|
Nocedal I, Mancera E, Johnson AD. Gene regulatory network plasticity predates a switch in function of a conserved transcription regulator. eLife 2017; 6:e23250. [PMID: 28327289 PMCID: PMC5391208 DOI: 10.7554/elife.23250] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 03/21/2017] [Indexed: 12/15/2022] Open
Abstract
The rewiring of gene regulatory networks can generate phenotypic novelty. It remains an open question, however, how the large number of connections needed to form a novel network arise over evolutionary time. Here, we address this question using the network controlled by the fungal transcription regulator Ndt80. This conserved protein has undergone a dramatic switch in function-from an ancestral role regulating sporulation to a derived role regulating biofilm formation. This switch in function corresponded to a large-scale rewiring of the genes regulated by Ndt80. However, we demonstrate that the Ndt80-target gene connections were undergoing extensive rewiring prior to the switch in Ndt80's regulatory function. We propose that extensive drift in the Ndt80 regulon allowed for the exploration of alternative network structures without a loss of ancestral function, thereby facilitating the formation of a network with a new function.
Collapse
Affiliation(s)
- Isabel Nocedal
- Department of Microbiology and Immunology, University of California, San Francisco, United States
- Department of Biochemistry and Biophysics, University of California, San Francisco, United States
| | - Eugenio Mancera
- Department of Microbiology and Immunology, University of California, San Francisco, United States
- Department of Biochemistry and Biophysics, University of California, San Francisco, United States
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, United States
- Department of Biochemistry and Biophysics, University of California, San Francisco, United States
| |
Collapse
|
39
|
Thompson DA, Cubillos FA. Natural gene expression variation studies in yeast. Yeast 2016; 34:3-17. [PMID: 27668700 DOI: 10.1002/yea.3210] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/16/2016] [Accepted: 09/18/2016] [Indexed: 11/06/2022] Open
Abstract
The rise of sequence information across different yeast species and strains is driving an increasing number of studies in the emerging field of genomics to associate polymorphic variants, mRNA abundance and phenotypic differences between individuals. Here, we gathered evidence from recent studies covering several layers that define the genotype-phenotype gap, such as mRNA abundance, allele-specific expression and translation efficiency to demonstrate how genetic variants co-evolve and define an individual's genome. Moreover, we exposed several antecedents where inter- and intra-specific studies led to opposite conclusions, probably owing to genetic divergence. Future studies in this area will benefit from the access to a massive array of well-annotated genomes and new sequencing technologies, which will allow the fine breakdown of the complex layers that delineate the genotype-phenotype map. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
| | - Francisco A Cubillos
- Centro de Estudios en Ciencia y Tecnología de Alimentos, Universidad de Santiago de Chile, Santiago, Chile.,Millennium Nucleus for Fungal Integrative and Synthetic Biology.,Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| |
Collapse
|
40
|
Medina EM, Turner JJ, Gordân R, Skotheim JM, Buchler NE. Punctuated evolution and transitional hybrid network in an ancestral cell cycle of fungi. eLife 2016; 5. [PMID: 27162172 PMCID: PMC4862756 DOI: 10.7554/elife.09492] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 04/07/2016] [Indexed: 12/12/2022] Open
Abstract
Although cell cycle control is an ancient, conserved, and essential process, some core animal and fungal cell cycle regulators share no more sequence identity than non-homologous proteins. Here, we show that evolution along the fungal lineage was punctuated by the early acquisition and entrainment of the SBF transcription factor through horizontal gene transfer. Cell cycle evolution in the fungal ancestor then proceeded through a hybrid network containing both SBF and its ancestral animal counterpart E2F, which is still maintained in many basal fungi. We hypothesize that a virally-derived SBF may have initially hijacked cell cycle control by activating transcription via the cis-regulatory elements targeted by the ancestral cell cycle regulator E2F, much like extant viral oncogenes. Consistent with this hypothesis, we show that SBF can regulate promoters with E2F binding sites in budding yeast. DOI:http://dx.doi.org/10.7554/eLife.09492.001 Living cells grow and divide with remarkable precision to ensure that their genetic material is faithfully duplicated and distributed equally to the newly formed daughter cells. This precision is achieved through a series of steps known as the cell cycle. The cell cycle is ancient and conserved across all Eukaryotes, including plants, animals and fungi. However, some of the core proteins present in animals and fungi are unrelated. This raises the question as to how a drastic change could have occurred and been tolerated over evolution. In animals and plants, a protein called E2F controls the expression of genes that are needed to begin the cell cycle. In most fungi, an equivalent protein called SBF performs the same role as E2F, but the two proteins are very different and do not appear to share a common ancestor. This is unexpected given that fungi and animals are more closely related to one another than either is to plants. Medina et al. searched the genomes of many animals, fungi, plants, algae, and their closest relatives for genes that encoded proteins like E2F and SBF. SBF-like proteins were only found in fungi, yet some fungal groups had cell cycle regulators like those found in animals. Zoosporic fungi, which diverged early from the fungal ancestor, had both SBF- and E2F-like proteins, while many fungi later lost E2F during evolution. So how did fungi acquire SBF? Medina et al. observed that part of the SBF protein is similar to proteins found in many viruses. The broad distribution of these viral SBF-like proteins suggests that they arose first in viruses, and a fungal ancestor acquired one such protein during a viral infection. As SBF and E2F bind similar DNA sequences, Medina et al. hypothesized that this viral SBF hijacked control of the cell cycle in the fungal ancestor by controlling expression of genes that were originally controlled only by E2F. In support of this idea, experiments showed that many E2F binding sites in modern genes are also SBF binding sites, and that E2F sites can substitute for SBF sites in SBF-controlled genes. Future experiments in zoosporic fungi, which have animal-like and fungal-like features, would provide a glimpse of how a fungal ancestor may have used both SBF and E2F. These experiments may also reveal why most fungi have retained the newer SBF but lost the ancestral and widely conserved E2F protein. DOI:http://dx.doi.org/10.7554/eLife.09492.002
Collapse
Affiliation(s)
- Edgar M Medina
- Department of Biology, Duke University, Durham, United States.,Center for Genomic and Computational Biology, Duke University, Durham, United States
| | | | - Raluca Gordân
- Center for Genomic and Computational Biology, Duke University, Durham, United States.,Department of Biostatistics and Bioinformatics, Duke University, Durham, United States
| | - Jan M Skotheim
- Department of Biology, Stanford University, Stanford, United States
| | - Nicolas E Buchler
- Department of Biology, Duke University, Durham, United States.,Center for Genomic and Computational Biology, Duke University, Durham, United States
| |
Collapse
|
41
|
Abstract
When transcription regulatory networks are compared among distantly related eukaryotes, a number of striking similarities are observed: a larger-than-expected number of genes, extensive overlapping connections, and an apparently high degree of functional redundancy. It is often assumed that the complexity of these networks represents optimized solutions, precisely sculpted by natural selection; their common features are often asserted to be adaptive. Here, we discuss support for an alternative hypothesis: the common structural features of transcription networks arise from evolutionary trajectories of "least resistance"--that is, the relative ease with which certain types of network structures are formed during their evolution.
Collapse
|
42
|
Bizzarri M, Giudici P, Cassanelli S, Solieri L. Chimeric Sex-Determining Chromosomal Regions and Dysregulation of Cell-Type Identity in a Sterile Zygosaccharomyces Allodiploid Yeast. PLoS One 2016; 11:e0152558. [PMID: 27065237 PMCID: PMC4827841 DOI: 10.1371/journal.pone.0152558] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 03/16/2016] [Indexed: 12/31/2022] Open
Abstract
Allodiploidization is a fundamental yet evolutionarily poorly characterized event, which impacts genome evolution and heredity, controlling organismal development and polyploid cell-types. In this study, we investigated the sex determination system in the allodiploid and sterile ATCC 42981 yeast, a member of the Zygosaccharomyces rouxii species complex, and used it to study how a chimeric mating-type gene repertoire contributes to hybrid reproductive isolation. We found that ATCC 42981 has 7 MAT-like (MTL) loci, 3 of which encode α-idiomorph and 4 encode a-idiomorph. Two phylogenetically divergent MAT expression loci were identified on different chromosomes, accounting for a hybrid a/α genotype. Furthermore, extra a-idimorph-encoding loci (termed MTLa copies 1 to 3) were recognized, which shared the same MATa1 ORFs but diverged for MATa2 genes. Each MAT expression locus was linked to a HML silent cassette, while the corresponding HMR loci were located on another chromosome. Two putative parental sex chromosome pairs contributed to this unusual genomic architecture: one came from an as-yet-undescribed taxon, which has the NCYC 3042 strain as a unique representative, while the other did not match any MAT-HML and HMR organizations previously described in Z. rouxii species. This chimeric rearrangement produces two copies of the HO gene, which encode for putatively functional endonucleases essential for mating-type switching. Although both a and α coding sequences, which are required to obtain a functional cell-type a1-α2 regulator, were present in the allodiploid ATCC 42981 genome, the transcriptional circuit, which regulates entry into meiosis in response to meiosis-inducing salt stress, appeared to be turned off. Furthermore, haploid and α-specific genes, such as MATα1 and HO, were observed to be actively transcribed and up-regulated under hypersaline stress. Overall, these evidences demonstrate that ATCC 42981 is unable to repress haploid α-specific genes and to activate meiosis in response to stress. We argue that sequence divergence within the chimeric a1-α2 heterodimer could be involved in the generation of negative epistasis, contributing to the allodiploid sterility and the dysregulation of cell identity.
Collapse
Affiliation(s)
- Melissa Bizzarri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Paolo Giudici
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Stefano Cassanelli
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Lisa Solieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| |
Collapse
|
43
|
Bartlett M, Thompson B, Brabazon H, Del Gizzi R, Zhang T, Whipple C. Evolutionary Dynamics of Floral Homeotic Transcription Factor Protein-Protein Interactions. Mol Biol Evol 2016; 33:1486-501. [PMID: 26908583 PMCID: PMC4868119 DOI: 10.1093/molbev/msw031] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Protein–protein interactions (PPIs) have widely acknowledged roles in the regulation of development, but few studies have addressed the timing and mechanism of shifting PPIs over evolutionary history. The B-class MADS-box transcription factors, PISTILLATA (PI) and APETALA3 (AP3) are key regulators of floral development. PI-like (PIL) and AP3-like (AP3L) proteins from a number of plants, including Arabidopsis thaliana (Arabidopsis) and the grass Zea mays (maize), bind DNA as obligate heterodimers. However, a PIL protein from the grass relative Joinvillea can bind DNA as a homodimer. To ascertain whether Joinvillea PIL homodimerization is an anomaly or indicative of broader trends, we characterized PIL dimerization across the Poales and uncovered unexpected evolutionary lability. Both obligate B-class heterodimerization and PIL homodimerization have evolved multiple times in the order, by distinct molecular mechanisms. For example, obligate B-class heterodimerization in maize evolved very recently from PIL homodimerization. A single amino acid change, fixed during domestication, is sufficient to toggle one maize PIL protein between homodimerization and obligate heterodimerization. We detected a signature of positive selection acting on residues preferentially clustered in predicted sites of contact between MADS-box monomers and dimers, and in motifs that mediate MADS PPI specificity in Arabidopsis. Changing one positively selected residue can alter PIL dimerization activity. Furthermore, ectopic expression of a Joinvillea PIL homodimer in Arabidopsis can homeotically transform sepals into petals. Our results provide a window into the evolutionary remodeling of PPIs, and show that novel interactions have the potential to alter plant form in a context-dependent manner.
Collapse
Affiliation(s)
- Madelaine Bartlett
- Department of Biology, University of Massachusetts Amherst Department of Biology, Brigham Young University
| | | | | | | | - Thompson Zhang
- Department of Biology, University of Massachusetts Amherst
| | | |
Collapse
|
44
|
Lohse MB, Kongsomboonvech P, Madrigal M, Hernday AD, Nobile CJ. Genome-Wide Chromatin Immunoprecipitation in Candida albicans and Other Yeasts. Methods Mol Biol 2016; 1361:161-184. [PMID: 26483022 PMCID: PMC4773921 DOI: 10.1007/978-1-4939-3079-1_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Chromatin immunoprecipitation experiments are critical to investigating the interactions between DNA and a wide range of nuclear proteins within a cell or biological sample. In this chapter we outline an optimized protocol for genome-wide chromatin immunoprecipitation that has been used successfully for several distinct morphological forms of numerous yeast species, and include an optimized method for amplification of chromatin immunoprecipitated DNA samples and hybridization to a high-density oligonucleotide tiling microarray. We also provide detailed suggestions on how to analyze the complex data obtained from these experiments.
Collapse
Affiliation(s)
- Matthew B Lohse
- Department of Microbiology and Immunology, University of California, San Francisco, 600 16th Street, San Francisco, CA, 94158, USA
| | - Pisiwat Kongsomboonvech
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, CA, 95343, USA
| | - Maria Madrigal
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, CA, 95343, USA
| | - Aaron D Hernday
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, CA, 95343, USA.
| | - Clarissa J Nobile
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, CA, 95343, USA.
| |
Collapse
|
45
|
Nocedal I, Johnson AD. How Transcription Networks Evolve and Produce Biological Novelty. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2015; 80:265-74. [PMID: 26657905 DOI: 10.1101/sqb.2015.80.027557] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The rewiring of gene regulatory networks over evolutionary timescales produces changes in the patterns of gene expression and is a major source of diversity among species. Yet the molecular mechanisms underlying evolutionary rewiring are only beginning to be understood. Here, we discuss recent analyses in ascomycete yeasts that have revealed several general principles of network rewiring. Specifically, we discuss how transcription networks can maintain a functional output despite changes in mechanism, how specific types of constraints alter available evolutionary trajectories, and how regulatory rewiring can ultimately lead to phenotypic novelty. We also argue that the structure and "logic" of extant gene regulatory networks can largely be accounted for by constraints that shape their evolutionary trajectories.
Collapse
Affiliation(s)
- Isabel Nocedal
- Departments of Microbiology and Immunology and of Biochemistry and Biophysics, University of California, San Francisco, California 94158
| | - Alexander D Johnson
- Departments of Microbiology and Immunology and of Biochemistry and Biophysics, University of California, San Francisco, California 94158
| |
Collapse
|
46
|
Roy S, Thompson D. Evolution of regulatory networks in Candida glabrata: learning to live with the human host. FEMS Yeast Res 2015; 15:fov087. [PMID: 26449820 DOI: 10.1093/femsyr/fov087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2015] [Indexed: 12/12/2022] Open
Abstract
The opportunistic human fungal pathogen Candida glabrata is second only to C. albicans as the cause of Candida infections and yet is more closely related to Saccharomyces cerevisiae. Recent advances in functional genomics technologies and computational approaches to decipher regulatory networks, and the comparison of these networks among these and other Ascomycete species, have revealed both unique and shared strategies in adaptation to a human commensal/opportunistic pathogen lifestyle and antifungal drug resistance in C. glabrata. Recently, several C. glabrata sister species in the Nakeseomyces clade representing both human associated (commensal) and environmental isolates have had their genomes sequenced and analyzed. This has paved the way for comparative functional genomics studies to characterize the regulatory networks in these species to identify informative patterns of conservation and divergence linked to phenotypic evolution in the Nakaseomyces lineage.
Collapse
Affiliation(s)
- Sushmita Roy
- Department of Biostatistics and Medical Informatics, University of Wisconsin Madison, Madison, WI 53715, USA Wisconsin Institute for Discovery, University of Wisconsin, Madison, WI 53715, USA
| | - Dawn Thompson
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| |
Collapse
|
47
|
Abstract
Candida species are the most prevalent human fungal pathogens, with Candida albicans being the most clinically relevant species. Candida albicans resides as a commensal of the human gastrointestinal tract but is a frequent cause of opportunistic mucosal and systemic infections. Investigation of C. albicans virulence has traditionally relied on candidate gene approaches, but recent advances in functional genomics have now facilitated global, unbiased studies of gene function. Such studies include comparative genomics (both between and within Candida species), analysis of total RNA expression, and regulation and delineation of protein-DNA interactions. Additionally, large collections of mutant strains have begun to aid systematic screening of clinically relevant phenotypes. Here, we will highlight the development of functional genomics in C. albicans and discuss the use of these approaches to addressing both commensalism and pathogenesis in this species.
Collapse
|
48
|
Thompson D, Regev A, Roy S. Comparative analysis of gene regulatory networks: from network reconstruction to evolution. Annu Rev Cell Dev Biol 2015; 31:399-428. [PMID: 26355593 DOI: 10.1146/annurev-cellbio-100913-012908] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Regulation of gene expression is central to many biological processes. Although reconstruction of regulatory circuits from genomic data alone is therefore desirable, this remains a major computational challenge. Comparative approaches that examine the conservation and divergence of circuits and their components across strains and species can help reconstruct circuits as well as provide insights into the evolution of gene regulatory processes and their adaptive contribution. In recent years, advances in genomic and computational tools have led to a wealth of methods for such analysis at the sequence, expression, pathway, module, and entire network level. Here, we review computational methods developed to study transcriptional regulatory networks using comparative genomics, from sequence to functional data. We highlight how these methods use evolutionary conservation and divergence to reliably detect regulatory components as well as estimate the extent and rate of divergence. Finally, we discuss the promise and open challenges in linking regulatory divergence to phenotypic divergence and adaptation.
Collapse
Affiliation(s)
- Dawn Thompson
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | | | | |
Collapse
|
49
|
Dey G, Meyer T. Phylogenetic Profiling for Probing the Modular Architecture of the Human Genome. Cell Syst 2015; 1:106-15. [PMID: 27135799 DOI: 10.1016/j.cels.2015.08.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 08/03/2015] [Accepted: 08/10/2015] [Indexed: 12/22/2022]
Abstract
Information about functional connections between genes can be derived from patterns of coupled loss of their homologs across multiple species. This comparative approach, termed phylogenetic profiling, has been successfully used to infer genetic interactions in bacteria and eukaryotes. Rapid progress in sequencing eukaryotic species has enabled the recent phylogenetic profiling of the human genome, resulting in systematic functional predictions for uncharacterized human genes. Importantly, groups of co-evolving genes reveal widespread modularity in the underlying genetic network, facilitating experimental analyses in human cells as well as comparative studies of conserved functional modules across species. This strategy is particularly successful in identifying novel metabolic proteins and components of multi-protein complexes. The targeted sequencing of additional key eukaryotes and the incorporation of improved methods to generate and compare phylogenetic profiles will further boost the predictive power and utility of this evolutionary approach to the functional analysis of gene interaction networks.
Collapse
Affiliation(s)
- Gautam Dey
- Chemical and Systems Biology, Stanford University, Stanford CA 94305, USA.
| | - Tobias Meyer
- Chemical and Systems Biology, Stanford University, Stanford CA 94305, USA.
| |
Collapse
|
50
|
Function does not follow form in gene regulatory circuits. Sci Rep 2015; 5:13015. [PMID: 26290154 PMCID: PMC4542331 DOI: 10.1038/srep13015] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 07/06/2015] [Indexed: 11/08/2022] Open
Abstract
Gene regulatory circuits are to the cell what arithmetic logic units are to the chip: fundamental components of information processing that map an input onto an output. Gene regulatory circuits come in many different forms, distinct structural configurations that determine who regulates whom. Studies that have focused on the gene expression patterns (functions) of circuits with a given structure (form) have examined just a few structures or gene expression patterns. Here, we use a computational model to exhaustively characterize the gene expression patterns of nearly 17 million three-gene circuits in order to systematically explore the relationship between circuit form and function. Three main conclusions emerge. First, function does not follow form. A circuit of any one structure can have between twelve and nearly thirty thousand distinct gene expression patterns. Second, and conversely, form does not follow function. Most gene expression patterns can be realized by more than one circuit structure. And third, multifunctionality severely constrains circuit form. The number of circuit structures able to drive multiple gene expression patterns decreases rapidly with the number of these patterns. These results indicate that it is generally not possible to infer circuit function from circuit form, or vice versa.
Collapse
|