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Apte RA, Smidler AL, Pai JJ, Chow ML, Chen S, Mondal A, Sánchez C. HM, Antoshechkin I, Marshall JM, Akbari OS. Eliminating malaria vectors with precision-guided sterile males. Proc Natl Acad Sci U S A 2024; 121:e2312456121. [PMID: 38917000 PMCID: PMC11228498 DOI: 10.1073/pnas.2312456121] [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: 07/20/2023] [Accepted: 05/03/2024] [Indexed: 06/27/2024] Open
Abstract
Controlling the principal African malaria vector, the mosquito Anopheles gambiae, is considered essential to curtail malaria transmission. However, existing vector control technologies rely on insecticides, which are becoming increasingly ineffective. Sterile insect technique (SIT) is a powerful suppression approach that has successfully eradicated a number of insect pests, yet the A. gambiae toolkit lacks the requisite technologies for its implementation. SIT relies on iterative mass releases of nonbiting, nondriving, sterile males which seek out and mate with monandrous wild females. Once mated, females are permanently sterilized due to mating-induced refractoriness, which results in population suppression of the subsequent generation. However, sterilization by traditional methods renders males unfit, making the creation of precise genetic sterilization methods imperative. Here, we introduce a vector control technology termed precision-guided sterile insect technique (pgSIT), in A. gambiae for inducible, programmed male sterilization and female elimination for wide-scale use in SIT campaigns. Using a binary CRISPR strategy, we cross separate engineered Cas9 and gRNA strains to disrupt male-fertility and female-essential genes, yielding >99.5% male sterility and >99.9% female lethality in hybrid progeny. We demonstrate that these genetically sterilized males have good longevity, are able to induce sustained population suppression in cage trials, and are predicted to eliminate wild A. gambiae populations using mathematical models, making them ideal candidates for release. This work provides a valuable addition to the malaria genetic biocontrol toolkit, enabling scalable SIT-like confinable, species-specific, and safe suppression in the species.
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Affiliation(s)
- Reema A. Apte
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA92093
| | - Andrea L. Smidler
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA92093
| | - James J. Pai
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA92093
| | - Martha L. Chow
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA92093
| | - Sanle Chen
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA92093
| | - Agastya Mondal
- Division of Epidemiology, School of Public Health, University of California, Berkeley, CA94720
- Division of Biostatistics, School of Public Health, University of California, Berkeley, CA94720
| | - Héctor M. Sánchez C.
- Division of Epidemiology, School of Public Health, University of California, Berkeley, CA94720
- Division of Biostatistics, School of Public Health, University of California, Berkeley, CA94720
| | - Igor Antoshechkin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA91125
| | - John M. Marshall
- Division of Epidemiology, School of Public Health, University of California, Berkeley, CA94720
- Division of Biostatistics, School of Public Health, University of California, Berkeley, CA94720
- Innovative Genomics Institute, University of California, Berkeley, CA94720
| | - Omar S. Akbari
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California San Diego, La Jolla, CA92093
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2
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Smidler AL, Apte RA, Pai JJ, Chow ML, Chen S, Mondal A, Sánchez C. HM, Antoshechkin I, Marshall JM, Akbari OS. Eliminating Malaria Vectors with Precision Guided Sterile Males. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.20.549947. [PMID: 37503146 PMCID: PMC10370176 DOI: 10.1101/2023.07.20.549947] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Controlling the principal African malaria vector, the mosquito Anopheles gambiae, is considered essential to curtail malaria transmission. However existing vector control technologies rely on insecticides, which are becoming increasingly ineffective. Sterile insect technique (SIT) is a powerful suppression approach that has successfully eradicated a number of insect pests, yet the A. gambiae toolkit lacks the requisite technologies for its implementation. SIT relies on iterative mass-releases of non-biting, non-driving, sterile males which seek out and mate with monandrous wild females. Once mated, females are permanently sterilized due to mating-induced refractoriness, which results in population suppression of the subsequent generation. However, sterilization by traditional methods renders males unfit, making the creation of precise genetic sterilization methods imperative. Here we develop precision guided Sterile Insect Technique (pgSIT) in the mosquito A. gambiae for inducible, programmed male-sterilization and female-elimination for wide scale use in SIT campaigns. Using a binary CRISPR strategy, we cross separate engineered Cas9 and gRNA strains to disrupt male-fertility and female-essential genes, yielding >99.5% male-sterility and >99.9% female-lethality in hybrid progeny. We demonstrate that these genetically sterilized males have good longevity, are able to induce population suppression in cage trials, and are predicted to eliminate wild A. gambiae populations using mathematical models, making them ideal candidates for release. This work provides a valuable addition to the malaria genetic biocontrol toolkit, for the first time enabling scalable SIT-like confinable suppression in the species.
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Affiliation(s)
- Andrea L. Smidler
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
| | - Reema A. Apte
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
| | - James J. Pai
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
| | - Martha L. Chow
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
| | - Sanle Chen
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
| | - Agastya Mondal
- Divisions of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Héctor M. Sánchez C.
- Divisions of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Igor Antoshechkin
- Division of Biology and Biological Engineering (BBE), California Institute of Technology, Pasadena, CA91125, USA
| | - John M. Marshall
- Divisions of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, CA 94720, USA
- Innovative Genomics Institute, University of California, Berkeley, CA 94720, USA
| | - Omar S. Akbari
- School of Biological Sciences, Department of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093
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3
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Voortman L, Johnston RJ. Transcriptional repression in stochastic gene expression, patterning, and cell fate specification. Dev Biol 2022; 481:129-138. [PMID: 34688689 PMCID: PMC8665150 DOI: 10.1016/j.ydbio.2021.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 10/04/2021] [Accepted: 10/09/2021] [Indexed: 01/03/2023]
Abstract
Development is often driven by signaling and lineage-specific cues, yielding highly uniform and reproducible outcomes. Development also involves mechanisms that generate noise in gene expression and random patterns across tissues. Cells sometimes randomly choose between two or more cell fates in a mechanism called stochastic cell fate specification. This process diversifies cell types in otherwise homogenous tissues. Stochastic mechanisms have been extensively studied in prokaryotes where noisy gene activation plays a pivotal role in controlling cell fates. In eukaryotes, transcriptional repression stochastically limits gene expression to generate random patterns and specify cell fates. Here, we review our current understanding of repressive mechanisms that produce random patterns of gene expression and cell fates in flies, plants, mice, and humans.
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Affiliation(s)
- Lukas Voortman
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA.
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4
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Fei Y, Pyott DE, Molnar A. Temperature modulates virus-induced transcriptional gene silencing via secondary small RNAs. THE NEW PHYTOLOGIST 2021; 232:356-371. [PMID: 34185326 DOI: 10.1111/nph.17586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 06/17/2021] [Indexed: 05/08/2023]
Abstract
Virus-induced gene silencing (VIGS) can be harnessed to sequence-specifically degrade host transcripts and induce heritable epigenetic modifications referred to as virus-induced post-transcriptional gene silencing (ViPTGS) and virus-induced transcriptional gene silencing (ViTGS), respectively. Both ViPTGS and ViTGS enable manipulation of endogenous gene expression without the need for transgenesis. Although VIGS has been widely used in many plant species, it is not always uniform or highly efficient. The efficiency of VIGS is affected by developmental, physiological and environmental factors. Here, we use recombinant Tobacco rattle viruses (TRV) to study the effect of temperature on ViPTGS and ViTGS using GFP as a reporter gene of silencing in N. benthamiana 16c plants. We found that unlike ViPTGS, ViTGS was impaired at high temperature. Using a novel mismatch-small interfering RNA (siRNA) tool, which precisely distinguishes virus-derived (primary) from target-generated (secondary) siRNAs, we demonstrated that the lack of secondary siRNA production/amplification was responsible for inefficient ViTGS at 29°C. Moreover, inefficient ViTGS at 29°C inhibited the transmission of epigenetic gene silencing to the subsequent generations. Our finding contributes to understanding the impact of environmental conditions on primary and secondary siRNA production and may pave the way to design/optimize ViTGS for transgene-free crop improvement.
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Affiliation(s)
- Yue Fei
- Institute of Molecular Plant Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Douglas E Pyott
- Institute of Molecular Plant Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Attila Molnar
- Institute of Molecular Plant Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
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5
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Li M, Yang T, Bui M, Gamez S, Wise T, Kandul NP, Liu J, Alcantara L, Lee H, Edula JR, Raban R, Zhan Y, Wang Y, DeBeaubien N, Chen J, Sánchez C HM, Bennett JB, Antoshechkin I, Montell C, Marshall JM, Akbari OS. Suppressing mosquito populations with precision guided sterile males. Nat Commun 2021; 12:5374. [PMID: 34508072 PMCID: PMC8433431 DOI: 10.1038/s41467-021-25421-w] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/23/2021] [Indexed: 01/06/2023] Open
Abstract
The mosquito Aedes aegypti is the principal vector for arboviruses including dengue/yellow fever, chikungunya, and Zika virus, infecting hundreds of millions of people annually. Unfortunately, traditional control methodologies are insufficient, so innovative control methods are needed. To complement existing measures, here we develop a molecular genetic control system termed precision-guided sterile insect technique (pgSIT) in Aedes aegypti. PgSIT uses a simple CRISPR-based approach to generate flightless females and sterile males that are deployable at any life stage. Supported by mathematical models, we empirically demonstrate that released pgSIT males can compete, suppress, and even eliminate mosquito populations. This platform technology could be used in the field, and adapted to many vectors, for controlling wild populations to curtail disease in a safe, confinable, and reversible manner. A. aegypti is the principal vector for arboviruses that impact on human health and wellbeing. Here the authors use precision guided sterile insect technique—pgSIT—to suppress or eliminate mosquito populations in multigeneration cage experiments.
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Affiliation(s)
- Ming Li
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Ting Yang
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Michelle Bui
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Stephanie Gamez
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Tyler Wise
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Nikolay P Kandul
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Junru Liu
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Lenissa Alcantara
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Haena Lee
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Jyotheeswara R Edula
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA.,Tata Institute for Genetics and Society, La Jolla, CA, USA.,Tata Institute for Genetics and Society (TIGS), TIGS Center at inStem, GKVK Campus, Bangalore, Karnataka, India
| | - Robyn Raban
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Yinpeng Zhan
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara, CA, USA
| | - Yijin Wang
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara, CA, USA
| | - Nick DeBeaubien
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara, CA, USA
| | - Jieyan Chen
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara, CA, USA
| | - Héctor M Sánchez C
- Divisions of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, CA, USA
| | - Jared B Bennett
- Divisions of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, CA, USA.,Biophysics Graduate Group, University of California, Berkeley, CA, USA
| | - Igor Antoshechkin
- Division of Biology and Biological Engineering (BBE), California Institute of Technology, Pasadena, CA, USA
| | - Craig Montell
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara, CA, USA
| | - John M Marshall
- Divisions of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, CA, USA.,Innovative Genomics Institute, University of California, Berkeley, CA, USA
| | - Omar S Akbari
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA. .,Tata Institute for Genetics and Society, La Jolla, CA, USA.
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6
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Solodovnikov AA, Gvozdev VA, Lavrov SA. High Level of Gene Transcription at the Embryonic Stage Leads to the Suppression of Heterochromatic Trans-Inactivation in Drosophila melanogaster Adults. BIOCHEMISTRY (MOSCOW) 2021; 85:472-479. [PMID: 32569554 DOI: 10.1134/s0006297920040070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In some cases, gene transfer from euchromatin to constitutive heterochromatin as a result of chromosomal rearrangement is accompanied by epigenetic inactivation of this gene (cis-inactivation). In the case of trans-inactivation, transgenes in the normal chromosome are repressed by the cis-inactivation-causing rearranged homologous chromosome. Trans-inactivation is a result of the somatic pairing of homologs and the transfer of the normal chromosomal segment to the heterochromatic compartment of the nucleus. Previously, we have shown that the degree of trans-inactivation of the UAS-eGFP reporter gene in adult flies depends on its transcription level that can be regulated by temperature using the GAL4 transcription activator and its temperature-sensitive inhibitor GAL80ts. In this paper, we investigated the epigenetic inheritance of the active/repressed state of the trans-inactivated reporter gene at different expression levels by measuring eGFP fluorescence in the individual cells of Malpighian tubules in adult flies. High expression levels at the embryonic stage protected the eGFP gene from trans-inactivation in adult flies. The activated state was inherited over the entire period of development and differentiation, while the activating effect of GAL4 was turned off.
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Affiliation(s)
- A A Solodovnikov
- Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, 123182, Russia
| | - V A Gvozdev
- Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, 123182, Russia
| | - S A Lavrov
- Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, 123182, Russia.
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7
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Eun K, Hong N, Jeong YW, Park MG, Hwang SU, Jeong YIK, Choi EJ, Olsson PO, Hwang WS, Hyun SH, Kim H. Transcriptional activities of human elongation factor-1α and cytomegalovirus promoter in transgenic dogs generated by somatic cell nuclear transfer. PLoS One 2020; 15:e0233784. [PMID: 32492024 PMCID: PMC7269240 DOI: 10.1371/journal.pone.0233784] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 05/12/2020] [Indexed: 11/30/2022] Open
Abstract
Recent advances in somatic cell nuclear transfer (SCNT) in canines facilitate the production of canine transgenic models. Owing to the importance of stable and strong promoter activity in transgenic animals, we tested human elongation factor 1α (hEF1α) and cytomegalovirus (CMV) promoter sequences in SCNT transgenic dogs. After transfection, transgenic donor fibroblasts with the hEF1α-enhanced green fluorescence protein (EGFP) transgene were successfully isolated using fluorescence-activated cell sorting (FACS). We obtained four puppies, after SCNT, and identified three puppies as being transgenic using PCR analysis. Unexpectedly, EGFP regulated by hEF1α promoter was not observed at the organismal and cellular levels in these transgenic dogs. EGFP expression was rescued by the inhibition of DNA methyltransferases, implying that the hEF1α promoter is silenced by DNA methylation. Next, donor cells with CMV-EGFP transgene were successfully established and SCNT was performed. Three puppies of six born puppies were confirmed to be transgenic. Unlike hEF1α-regulated EGFP, CMV-regulated EGFP was strongly detectable at both the organismal and cellular levels in all transgenic dogs, even after 19 months. In conclusion, our study suggests that the CMV promoter is more suitable, than the hEF1α promoter, for stable transgene expression in SCNT-derived transgenic canine model.
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Affiliation(s)
- Kiyoung Eun
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Institute of Animal Molecular Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
| | - Nayoung Hong
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Institute of Animal Molecular Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
| | - Yeon Woo Jeong
- Sooam Biotech Research Foundation, Guro-gu, Seoul, Republic of Korea
| | - Min Gi Park
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Institute of Animal Molecular Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
| | - Seon-Ung Hwang
- Laboratory of Veterinary Embryology and Biotechnology, College of Veterinary Medicine, Chungbuk National University, Seowon-gu, Cheongju, Republic of Korea
- Institute of Stem Cell & Regenerative Medicine, Chungbuk National University, Seowon-gu, Cheongju, Republic of Korea
| | - Yeon I. K. Jeong
- Sooam Biotech Research Foundation, Guro-gu, Seoul, Republic of Korea
| | - Eun Ji Choi
- Sooam Biotech Research Foundation, Guro-gu, Seoul, Republic of Korea
| | - P. Olof Olsson
- Sooam Biotech Research Foundation, Guro-gu, Seoul, Republic of Korea
| | - Woo Suk Hwang
- Sooam Biotech Research Foundation, Guro-gu, Seoul, Republic of Korea
| | - Sang-Hwan Hyun
- Laboratory of Veterinary Embryology and Biotechnology, College of Veterinary Medicine, Chungbuk National University, Seowon-gu, Cheongju, Republic of Korea
- Institute of Stem Cell & Regenerative Medicine, Chungbuk National University, Seowon-gu, Cheongju, Republic of Korea
- * E-mail: (SHH); (HK)
| | - Hyunggee Kim
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Institute of Animal Molecular Biotechnology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- * E-mail: (SHH); (HK)
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Wójcik E, Smalec E. Constitutive heterochromatin in chromosomes of duck hybrids and goose hybrids. Poult Sci 2016; 96:18-26. [PMID: 27664202 DOI: 10.3382/ps/pew318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/14/2016] [Accepted: 07/28/2016] [Indexed: 02/05/2023] Open
Abstract
Constitutive heterochromatin is a highly condensed fraction of chromatin in chromosomes. It is characterized by a high degree of polymorphism. Heterochromatin is located in the centromeric, telomeric, and interstitial parts of chromosomes. We used the CBG ( C: banding using B: arium hydroxide by G: iemsa) staining technique to identify heterochromatin in chromosomes. Analysis of karyotypes of F1 hybrids resulting from intergeneric hybridization of ducks (A. platyrhynchos × C. moschata) and interspecific crosses of geese (A. anser × A. cygnoides) were used to compare the karyotypes of 2 species of duck and 2 species of geese, as well as to compare the hybrids with the parent species. The localization of C-bands and their size were determined. In the duck hybrid, greater amounts of heterochromatin were noted in the homologous chromosomes from the duck A. platyrhynchos than in the chromosomes from the duck C. moschata. In the goose hybrid more heterochromatin was observed in the homologous chromosomes from the goose A. cygnoides than in the chromosomes from the goose A. anser. Comparison of chromosomes from the duck hybrid with chromosomes of the ducks A. platyrhynchos and C. moschata revealed nearly twice as much constitutive heterochromatin in the chromosomes of the hybrid. When chromosomes from the goose hybrid were compared with those of the geese A. anser and A. cygnoides, differences in the average content of heterochromatin were observed on only a few chromosomes.
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Affiliation(s)
- E Wójcik
- Department of Animal Genetics and Horse Breeding, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland
| | - E Smalec
- Department of Animal Genetics and Horse Breeding, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland
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9
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Lonardo F, Di Natale P, Lualdi S, Acquaviva F, Cuoco C, Scarano F, Maioli M, Pavone LM, Di Gregorio G, Filocamo M, Scarano G. Mucopolysaccharidosis type II in a female patient with a reciprocal X;9 translocation and skewed X chromosome inactivation. Am J Med Genet A 2014; 164A:2627-32. [PMID: 25044788 DOI: 10.1002/ajmg.a.36667] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 06/09/2014] [Indexed: 11/08/2022]
Abstract
Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is a rare X-linked disorder caused by deficient activity of the lysosomal enzyme, iduronate-2-sulfatase (IDS). Phenotypic expression of MPS II in female patients rarely occurs and may be the result of (i) structural abnormalities of the X chromosome, (ii) homozygosity for disease-causing mutations, or (iii) skewed X-chromosome inactivation, in which the normal IDS allele is preferentially inactivated and the abnormal IDS allele is active. We report here on a female patient with clinical MPS II manifestations, deficiency of IDS enzyme activity and a de novo balanced reciprocal X;9 translocation. As our patient has a skewed XCI pattern, but neither genomic IDS mutations nor abnormal IDS transcripts were detected, we speculate about the possible role of the chromosomal rearrangement in reducing the IDS translation efficiency.
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10
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Giovannini S, Marangio L, Fusco C, Scarano A, Frattini D, Della Giustina E, Zollino M, Neri G, Gobbi G. Epilepsy in ring 14 syndrome: a clinical and EEG study of 22 patients. Epilepsia 2013; 54:2204-13. [PMID: 24116895 DOI: 10.1111/epi.12393] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2013] [Indexed: 11/28/2022]
Abstract
PURPOSE To characterize epileptic phenotype, electroencephalography (EEG) features, and epileptic evolution in patients with ring 14 r(14) syndrome. METHODS Twenty-two patients with ring chromosome 14 were enrolled in the study. We examined age at onset, seizure semiology and frequency at onset and at follow-up, drug responsiveness/resistance, and interictal/ictal EEG data. The degree of severity of the epileptic phenotype negatively influences child cognitive development. KEY FINDINGS The incidence of epilepsy in patients with r(14) syndrome is virtually 100%, characterized by early onset, polymorphic seizures, and drug-resistant seizures. In addition, we ascertained focal secondarily generalized epilepsy, seizure cluster tendency, frequent status epilepticus, and a rather typical epilepsy evolution. EEG abnormalities consisted of slow background activity with pseudoperiodic bursts of generalized slow waves in the early stage, focal frontotemporal or temporoposterior slow waves with multifocal spikes interposed, and unusual rhythmic fast recruiting posterior spikes followed by secondary generalization. The degree of severity of the epileptic phenotype negatively influences child cognitive development. SIGNIFICANCE This study provides a more precise definition of seizure types, natural history, and drug responsiveness of r(14) syndrome, a highly epileptogenic chromosomal condition.
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Affiliation(s)
- Simona Giovannini
- Child Neurology Unit, IRCCS Institute of Neurological Sciences of Bologna, Bologna, Italy
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11
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Seong KH, Li D, Shimizu H, Nakamura R, Ishii S. Inheritance of stress-induced, ATF-2-dependent epigenetic change. Cell 2011; 145:1049-61. [PMID: 21703449 DOI: 10.1016/j.cell.2011.05.029] [Citation(s) in RCA: 220] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 03/16/2011] [Accepted: 05/23/2011] [Indexed: 11/17/2022]
Abstract
Atf1, the fission yeast homolog of activation transcription factor-2 (ATF-2), contributes to heterochromatin formation. However, the role of ATF-2 in chromatin assembly in higher organisms remains unknown. This study reveals that Drosophila ATF-2 (dATF-2) is required for heterochromatin assembly, whereas the stress-induced phosphorylation of dATF-2, via Mekk1-p38, disrupts heterochromatin. The dATF-2 protein colocalized with HP1, not only on heterochromatin but also at specific loci in euchromatin. Heat shock or osmotic stress induced phosphorylation of dATF-2 and resulted in its release from heterochromatin. This heterochromatic disruption was an epigenetic event that was transmitted to the next generation in a non-Mendelian fashion. When embryos were exposed to heat stress over multiple generations, the defective chromatin state was maintained over multiple successive generations, though it gradually returned to the normal state. The results suggest a mechanism by which the effects of stress are inherited epigenetically via the regulation of a tight chromatin structure.
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Affiliation(s)
- Ki-Hyeon Seong
- Laboratory of Molecular Genetics, RIKEN Tsukuba Institute, 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074, Japan
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Guilherme RS, Bragagnolo S, Pellegrino R, Christofolini DM, Takeno SS, Carvolheira GM, Kulikowski LD, Melaragno MI. Clinical, cytogenetic and molecular study in a case of r(3) with 3p deletion and review of the literature. Cytogenet Genome Res 2011; 134:325-30. [PMID: 21849783 DOI: 10.1159/000329478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2011] [Indexed: 11/19/2022] Open
Abstract
Ring chromosome 3 is a rare abnormality with only 10 patients described in the literature. We report a patient with r(3) and ∼6-Mb distal 3p deletion. Single nucleotide polymorphism array, multiplex ligation-dependent probe amplification and fluorescence in situ hybridization techniques revealed that the ring was formed by a break in 3p26.1 and fusion with the subtelomeric region of 3q. The patient presents delayed psychomotor development, growth failure, minor anomalies and other features similar to patients with 3p monosomy. The analysis of 300 metaphase cells using G-banding and fluorescence in situ hybridization with centromeric probe revealed ring instability resulting in cells with secondary aberrations and with ring loss that could also be related to some phenotypic characteristics such as growth delay. This is the first patient with r(3) studied using molecular techniques that determined the exact breakpoints in order to establish a better karyotype-phenotype correlation.
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Affiliation(s)
- R Santos Guilherme
- Department of Morphology and Genetics, Universidade Federal de São Paulo, Brazil
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Kloc A, Martienssen R. RNAi, heterochromatin and the cell cycle. Trends Genet 2008; 24:511-7. [PMID: 18778867 DOI: 10.1016/j.tig.2008.08.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 08/04/2008] [Accepted: 08/05/2008] [Indexed: 01/15/2023]
Abstract
For many decades after its initial characterization, heterochromatin was considered to be transcriptionally inert, but newer work indicates that this highly condensed chromosomal material is transcribed, and rapidly silenced, by an orchestrated sequence of events directed by RNA interference (RNAi). Recent studies shed light on the timely assembly and inheritance of heterochromatin within a short period during the cell cycle, thereby providing an explanation for how 'silent' heterochromatin can be transcribed during the S phase of the cell cycle. Together, these findings suggest a model of RNAi-directed epigenetic inheritance.
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Affiliation(s)
- Anna Kloc
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
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Affiliation(s)
- Ingela Djupedal
- Department of Biosciences and Medical Nutrition, Karolinska Institutet, Sweden/School of Life Sciences, University College Sodertorn, NOVUM, 141 57 Huddinge, Sweden
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Condon KC, Condon GC, Dafa'alla TH, Fu G, Phillips CE, Jin L, Gong P, Alphey L. Genetic sexing through the use of Y-linked transgenes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2007; 37:1168-1176. [PMID: 17916503 DOI: 10.1016/j.ibmb.2007.07.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Revised: 07/03/2007] [Accepted: 07/06/2007] [Indexed: 05/25/2023]
Abstract
Sterile insect technique (SIT)-based pest control programs rely on the mass release of sterile insects to reduce the wild target population. In many cases, it is desirable to release only males. Sterile females may cause damage, e.g., disease transmission by mosquitoes or crop damage via oviposition by the Mediterranean fruit fly (Medfly). Also, sterile females may decrease the effectiveness of released males by distracting them from seeking out wild females. To eliminate females from the release population, a suitable sexual dimorphism is required. For several pest species, genetic sexing strains have been constructed in which such a dimorphism has been induced by genetics. Classical strains were based on the translocation to the Y chromosome of a selectable marker, which is therefore expressed only in males. Recently, several prototype strains have been constructed using sex-specific expression of markers or conditional lethal genes from autosomal insertions of transgenes. Here, we describe a novel genetic sexing strategy based on the use of Y-linked transgenes expressing fluorescent proteins. We demonstrate the feasibility of this strategy in a major pest species, Ceratitis capitata (Wiedemann), and discuss the advantages and disadvantages relative to other genetic sexing methods and potential applicability to other species.
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Affiliation(s)
- Kirsty C Condon
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
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Srikantha T, Borneman AR, Daniels KJ, Pujol C, Wu W, Seringhaus MR, Gerstein M, Yi S, Snyder M, Soll DR. TOS9 regulates white-opaque switching in Candida albicans. EUKARYOTIC CELL 2006; 5:1674-87. [PMID: 16950924 PMCID: PMC1595353 DOI: 10.1128/ec.00252-06] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In Candida albicans, the a1-alpha2 complex represses white-opaque switching, as well as mating. Based upon the assumption that the a1-alpha2 corepressor complex binds to the gene that regulates white-opaque switching, a chromatinimmunoprecipitation-microarray analysis strategy was used to identify 52 genes that bound to the complex. One of these genes, TOS9, exhibited an expression pattern consistent with a "master switch gene." TOS9 was only expressed in opaque cells, and its gene product, Tos9p, localized to the nucleus. Deletion of the gene blocked cells in the white phase, misexpression in the white phase caused stable mass conversion of cells to the opaque state, and misexpression blocked temperature-induced mass conversion from the opaque state to the white state. A model was developed for the regulation of spontaneous switching between the opaque state and the white state that includes stochastic changes of Tos9p levels above and below a threshold that induce changes in the chromatin state of an as-yet-unidentified switching locus. TOS9 has also been referred to as EAP2 and WOR1.
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Affiliation(s)
- Thyagarajan Srikantha
- Department of Biological Sciences, 302 BBE, The University of Iowa, Iowa City, IA 52242, USA
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Schlade-Bartusiak K, Costa T, Summers AM, Nowaczyk MJM, Cox DW. FISH-mapping of telomeric 14q32 deletions: Search for the cause of seizures. Am J Med Genet A 2005; 138A:218-24. [PMID: 16152642 DOI: 10.1002/ajmg.a.30942] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Ring chromosome 14 is a rare cytogenetic disorder. Individuals with r(14) generally have developmental delay and seizures. Other features include hypotonia, microcephaly, mild facial dysmorphism, and retinal pigmentation. Most of these features are also found in patients with linear terminal deletions of chromosome 14, except for seizures and retinal abnormalities. The objective of the study was to determine if deletion of a specific chromosome region is a possible explanation for the occurrence of seizures in patients with ring chromosome 14. Patients diagnosed either with r(14) (six patients) or a deletion of distal 14q (three patients) were analyzed by FISH (fluorescence in situ hybridization) with BAC probes. We observed differences in the size of deletions in the studied group. In two r(14) patients, we did not detect any deletion; the four other patients had deletions of various sizes, ranging from 0.8 Mb to 5 Mb. Two linear deletions were 3.2 Mb and 5.3 Mb in length, respectively; the third case had an interstitial deletion that did not overlap with the others. The deleted regions in ring chromosomes showed overlap with those in the two linear terminal deletions. We conclude that there is unlikely to be a specific deleted locus in 14q32.3 that predisposes r(14) patients to seizures or retinal pigmentation. The cause is probably related to the formation of the ring itself and the effect this may have on local chromatin structure.
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