1
|
Atajanova T, Kang EM, Postnikova A, Price AL, Doerr S, Du M, Ugenti A, Ragkousi K. Lateral cell polarization drives organization of epithelia in sea anemone embryos and embryonic cell aggregates. bioRxiv 2024:2024.04.07.588493. [PMID: 38645007 PMCID: PMC11030385 DOI: 10.1101/2024.04.07.588493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
One of the first organizing processes during animal development is the assembly of embryonic cells into epithelia. In certain animals, including Hydra and sea anemones, epithelia also emerge when cells from dissociated tissues are aggregated back together. Although cell adhesion is required to keep cells together, it is not clear whether cell polarization plays a role as epithelia emerge from disordered aggregates. Here, we demonstrate that lateral cell polarization is essential for epithelial organization in both embryos and aggregates of the sea anemone Nematostella vectensis. Specifically, knock down of the lateral polarity protein Lgl disrupts epithelia in developing embryos and impairs the capacity of dissociated cells to epithelialize from aggregates. Cells in lgl mutant epithelia lose their columnar shape and have mispositioned mitotic spindles and ciliary basal bodies. Together, our data suggest that in Nematostella, Lgl is required to establish lateral cell polarity and position cytoskeletal organelles in cells of embryos and aggregates during de novo epithelial organization.
Collapse
Affiliation(s)
- Tavus Atajanova
- Department of Biology, Amherst College, Amherst, MA 01002, USA
- Present address: Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | | | - Anna Postnikova
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | | | - Sophia Doerr
- Department of Biology, Amherst College, Amherst, MA 01002, USA
- Present address: Department of Biology, Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Michael Du
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | - Alicia Ugenti
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | | |
Collapse
|
2
|
Doerr S, Zhou P, Ragkousi K. Origin and development of primary animal epithelia. Bioessays 2024; 46:e2300150. [PMID: 38009581 DOI: 10.1002/bies.202300150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/11/2023] [Accepted: 11/13/2023] [Indexed: 11/29/2023]
Abstract
Epithelia are the first organized tissues that appear during development. In many animal embryos, early divisions give rise to a polarized monolayer, the primary epithelium, rather than a random aggregate of cells. Here, we review the mechanisms by which cells organize into primary epithelia in various developmental contexts. We discuss how cells acquire polarity while undergoing early divisions. We describe cases where oriented divisions constrain cell arrangement to monolayers including organization on top of yolk surfaces. We finally discuss how epithelia emerge in embryos from animals that branched early during evolution and provide examples of epithelia-like arrangements encountered in single-celled eukaryotes. Although divergent and context-dependent mechanisms give rise to primary epithelia, here we trace the unifying principles underlying their formation.
Collapse
Affiliation(s)
- Sophia Doerr
- Department of Biology, Amherst College, Amherst, Massachusetts, USA
- Department of Biology, Institute of Molecular Biology, University of Oregon, Eugene, USA
| | - Phillip Zhou
- Department of Biology, Amherst College, Amherst, Massachusetts, USA
| | | |
Collapse
|
3
|
Zimmermann B, Montenegro JD, Robb SMC, Fropf WJ, Weilguny L, He S, Chen S, Lovegrove-Walsh J, Hill EM, Chen CY, Ragkousi K, Praher D, Fredman D, Schultz D, Moran Y, Simakov O, Genikhovich G, Gibson MC, Technau U. Topological structures and syntenic conservation in sea anemone genomes. Nat Commun 2023; 14:8270. [PMID: 38092765 PMCID: PMC10719294 DOI: 10.1038/s41467-023-44080-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 11/29/2023] [Indexed: 12/17/2023] Open
Abstract
There is currently little information about the evolution of gene clusters, genome architectures and karyotypes in early branching animals. Slowly evolving anthozoan cnidarians can be particularly informative about the evolution of these genome features. Here we report chromosome-level genome assemblies of two related anthozoans, the sea anemones Nematostella vectensis and Scolanthus callimorphus. We find a robust set of 15 chromosomes with a clear one-to-one correspondence between the two species. Both genomes show chromosomal conservation, allowing us to reconstruct ancestral cnidarian and metazoan chromosomal blocks, consisting of at least 19 and 16 ancestral linkage groups, respectively. We show that, in contrast to Bilateria, the Hox and NK clusters of investigated cnidarians are largely disintegrated, despite the presence of staggered hox/gbx expression in Nematostella. This loss of microsynteny conservation may be facilitated by shorter distances between cis-regulatory sequences and their cognate transcriptional start sites. We find no clear evidence for topologically associated domains, suggesting fundamental differences in long-range gene regulation compared to vertebrates. These data suggest that large sets of ancestral metazoan genes have been retained in ancestral linkage groups of some extant lineages; yet, higher order gene regulation with associated 3D architecture may have evolved only after the cnidarian-bilaterian split.
Collapse
Affiliation(s)
- Bob Zimmermann
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
- Research platform SinCeReSt, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Juan D Montenegro
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
- Research platform SinCeReSt, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Sofia M C Robb
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Whitney J Fropf
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Lukas Weilguny
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Shuonan He
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Shiyuan Chen
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Jessica Lovegrove-Walsh
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Eric M Hill
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Cheng-Yi Chen
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Katerina Ragkousi
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
- Department of Biology, Amherst College, Amherst, MA, 01002, USA
| | - Daniela Praher
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - David Fredman
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Darrin Schultz
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Yehu Moran
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
- The Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Oleg Simakov
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
- Research platform SinCeReSt, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Grigory Genikhovich
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Matthew C Gibson
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA.
| | - Ulrich Technau
- Department of Neurosciences and Developmental Biology, Faculty of Life Sciences, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria.
- Research platform SinCeReSt, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria.
- Max Perutz laboratories, University of Vienna, Dr. Bohrgasse 5, 1030, Vienna, Austria.
| |
Collapse
|
4
|
Doerr S, Ragkousi K. Cell polarity oscillations in mitotic epithelia. Curr Opin Genet Dev 2019; 57:47-53. [PMID: 31465986 DOI: 10.1016/j.gde.2019.07.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/15/2019] [Accepted: 07/15/2019] [Indexed: 12/21/2022]
Abstract
Epithelial organization and function depend on coordinated cell polarity. In developing tissues, proliferative epithelia maintain whole tissue polarity as individual cells undergo symmetric divisions. However, recent work has shown that cells in diverse epithelia remodel their polarity in a cell cycle-dependent manner. Here, we discuss the different mechanisms that drive mitotic polarity oscillations and their implications for tissue morphogenesis.
Collapse
Affiliation(s)
- Sophia Doerr
- Department of Biology, Amherst College, Amherst, MA 01002, United States; Program in Biochemistry and Biophysics, Amherst College, Amherst, MA 01002, United States
| | - Katerina Ragkousi
- Department of Biology, Amherst College, Amherst, MA 01002, United States; Program in Biochemistry and Biophysics, Amherst College, Amherst, MA 01002, United States.
| |
Collapse
|
5
|
Affiliation(s)
| | - Matthew C Gibson
- a Stowers Institute for Medical Research , Kansas City , MO , USA.,b Department of Anatomy and Cell Biology , The University of Kansas School of Medicine , Kansas City , MO , USA
| |
Collapse
|
6
|
Abstract
Epithelia are polarized layers of adherent cells that are the building blocks for organ and appendage structures throughout animals. To preserve tissue architecture and barrier function during both homeostasis and rapid growth, individual epithelial cells divide in a highly constrained manner. Building on decades of research focused on single cells, recent work is probing the mechanisms by which the dynamic process of mitosis is reconciled with the global maintenance of epithelial order during development. These studies reveal how symmetrically dividing cells both exploit and conform to tissue organization to orient their mitotic spindles during division and establish new adhesive junctions during cytokinesis.
Collapse
Affiliation(s)
| | - Matthew C Gibson
- Stowers Institute for Medical Research, Kansas City, MO 64110 Department of Anatomy and Cell Biology, Kansas University Medical Center, Kansas City, KS 66160
| |
Collapse
|
7
|
Ragkousi K, Davidson B. Endoderm morphogenesis and its effect on heart precursor cell migration in the ascidian Ciona intestinalis. Dev Biol 2010. [DOI: 10.1016/j.ydbio.2010.05.093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
8
|
Atluri S, Ragkousi K, Cortezzo DE, Setlow P. Cooperativity between different nutrient receptors in germination of spores of Bacillus subtilis and reduction of this cooperativity by alterations in the GerB receptor. J Bacteriol 2006; 188:28-36. [PMID: 16352818 PMCID: PMC1317597 DOI: 10.1128/jb.188.1.28-36.2006] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The GerA nutrient receptor alone triggers germination of Bacillus subtilis spores with L-alanine or L-valine, and these germinations were stimulated by glucose and K+ plus the GerK nutrient receptor. The GerB nutrient receptor alone did not trigger spore germination with any nutrients but required glucose, fructose, and K+ (GFK) (termed cogerminants) plus GerK for triggering of germination with a number of L-amino acids. GerB and GerA also triggered spore germination cooperatively with l-asparagine, fructose, and K+ and either L-alanine or L-valine. Two GerB variants (termed GerB*s) that were previously isolated by their ability to trigger spore germination in response to D-alanine do not respond to D-alanine but respond to the same L-amino acids that stimulate germination via GerB plus GerK and GFK. GerB*s alone triggered spore germination with these L-amino acids, although GerK plus GFK stimulated the rates of these germinations. In contrast to l-alanine germination via GerA, spore germination via L-alanine and GerB or GerB* was not inhibited by D-alanine. These data support the following conclusions. (i) Interaction with GerK, glucose, and K+ somehow stimulates spore germination via GerA. (ii) GerB can bind and respond to L-amino acids, although normally either the binding site is inaccessible or its occupation is not sufficient to trigger spore germination. (iii) Interaction of GerB with GerK and GFK allows GerB to bind or respond to amino acids. (iv) In addition to spore germination due to the interaction between GerA and GerK, and GerB and GerK, GerB can interact with GerA to trigger spore germination in response to appropriate nutrients. (v) The amino acid sequence changes in GerB*s reduce these receptor variants' requirement for GerK and cogerminants in their response to L-amino acids. (vi) GerK binds glucose, GerB interacts with fructose in addition to L-amino acids, and GerA interacts only with L-valine, L-alanine, and its analogs. (vii) The amino acid binding sites in GerA and GerB are different, even though both respond to L-alanine. These new conclusions are integrated into models for the signal transduction pathways that initiate spore germination.
Collapse
Affiliation(s)
- Swaroopa Atluri
- Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030-3305, USA
| | | | | | | |
Collapse
|
9
|
Klobutcher LA, Ragkousi K, Setlow P. The Bacillus subtilis spore coat provides "eat resistance" during phagocytic predation by the protozoan Tetrahymena thermophila. Proc Natl Acad Sci U S A 2006; 103:165-70. [PMID: 16371471 PMCID: PMC1324984 DOI: 10.1073/pnas.0507121102] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Indexed: 11/18/2022] Open
Abstract
Bacillus spores are highly resistant to many environmental stresses, owing in part to the presence of multiple "extracellular" layers. Although the role of some of these extracellular layers in resistance to particular stresses is known, the function of one of the outermost layers, the spore coat, is not completely understood. This study sought to determine whether the spore coat plays a role in resistance to predation by the ciliated protozoan Tetrahymena, which uses phagocytosis to ingest and degrade other microorganisms. Wild-type dormant spores of Bacillus subtilis were efficiently ingested by the protozoan Tetrahymena thermophila but were neither digested nor killed. However, spores with various coat defects were killed and digested, leaving only an outer shell termed a rind, and supporting the growth of Tetrahymena. A similar rind was generated when coat-defective spores were treated with lysozyme alone. The sensitivity of spores with different coat defects to predation by T. thermophila paralleled the spores' sensitivities to lysozyme. Spore killing by T. thermophila was by means of lytic enzymes within the protozoal phagosome, not by initial spore germination followed by killing. These findings suggest that a major function of the coat of spores of Bacillus species is to protect spores against predation. We also found that indigestible rinds were generated even from spores in which cross-linking of coat proteins was greatly reduced, implying the existence of a coat structure that is highly resistant to degradative enzymes.
Collapse
Affiliation(s)
- Lawrence A Klobutcher
- Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030-3305, USA
| | | | | |
Collapse
|
10
|
Abstract
The spores of Bacillus subtilis show remarkable resistance to many environmental stresses, due in part to the presence of an outer proteinaceous structure known as the spore coat. GerQ is a spore coat protein essential for the presence of CwlJ, an enzyme involved in the hydrolysis of the cortex during spore germination, in the spore coat. Here we show that GerQ is cross-linked into higher-molecular-mass forms due in large part to a transglutaminase. GerQ is the only substrate for this transglutaminase identified to date. In addition, we show that cross-linking of GerQ into high-molecular-mass forms occurs only very late in sporulation, after mother cell lysis. These findings, as well as studies of GerQ cross-linking in mutant strains where spore coat assembly is perturbed, lead us to suggest that coat proteins must assemble first and that their cross-linking follows as a final step in the spore coat formation pathway.
Collapse
Affiliation(s)
- Katerina Ragkousi
- Department of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, CT 06032, USA
| | | |
Collapse
|
11
|
Ragkousi K, Eichenberger P, van Ooij C, Setlow P. Identification of a new gene essential for germination of Bacillus subtilis spores with Ca2+-dipicolinate. J Bacteriol 2003; 185:2315-29. [PMID: 12644503 PMCID: PMC151495 DOI: 10.1128/jb.185.7.2315-2329.2003] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis spores can germinate with a 1:1 chelate of Ca(2+) and dipicolinic acid (DPA), a compound present at high levels in the spore core. Using a genetic screen to identify genes encoding proteins that are specifically involved in spore germination by Ca(2+)-DPA, three mutations were identified. One was in the gene encoding the cortex lytic enzyme, CwlJ, that was previously shown to be essential for spore germination by Ca(2+)-DPA. The other two were mapped to an open reading frame, ywdL, encoding a protein of unknown function. Analysis of ywdL expression showed that the gene is expressed during sporulation in the mother cell compartment of the sporulating cell and that its transcription is sigma(E) dependent. Functional characterization of YwdL demonstrated that it is a new spore coat protein that is essential for the presence of CwlJ in the spore coat. Assembly of YwdL itself into the spore coat is dependent on the coat morphogenetic proteins CotE and SpoIVA. However, other than lacking CwlJ, ywdL spores have no obvious defect in their spore coat. Because of the role for YwdL in a part of the spore germination process, we propose renaming ywdL as a spore germination gene, gerQ.
Collapse
Affiliation(s)
- Katerina Ragkousi
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032, USA
| | | | | | | |
Collapse
|
12
|
Paidhungat M, Ragkousi K, Setlow P. Genetic requirements for induction of germination of spores of Bacillus subtilis by Ca(2+)-dipicolinate. J Bacteriol 2001; 183:4886-93. [PMID: 11466292 PMCID: PMC99543 DOI: 10.1128/jb.183.16.4886-4893.2001] [Citation(s) in RCA: 233] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2001] [Accepted: 05/30/2001] [Indexed: 11/20/2022] Open
Abstract
Dormant Bacillus subtilis spores can be induced to germinate by nutrients, as well as by nonmetabolizable chemicals, such as a 1:1 chelate of Ca(2+) and dipicolinic acid (DPA). Nutrients bind receptors in the spore, and this binding triggers events in the spore core, including DPA excretion and rehydration, and also activates hydrolysis of the surrounding cortex through mechanisms that are largely unknown. As Ca(2+)-DPA does not require receptors to induce spore germination, we asked if this process utilizes other proteins, such as the putative cortex-lytic enzymes SleB and CwlJ, that are involved in nutrient-induced germination. We found that Ca(2+)-DPA triggers germination by first activating CwlJ-dependent cortex hydrolysis; this mechanism is different from nutrient-induced germination where cortex hydrolysis is not required for the early germination events in the spore core. Nevertheless, since nutrients can induce release of the spore's DPA before cortex hydrolysis, we examined if the DPA excreted from the core acts as a signal to activate CwlJ in the cortex. Indeed, endogenous DPA is required for nutrient-induced CwlJ activation and this requirement was partially remedied by exogenous Ca(2+)-DPA. Our findings thus define a mechanism for Ca(2+)-DPA-induced germination and also provide the first definitive evidence for a signaling pathway that activates cortex hydrolysis in response to nutrients.
Collapse
Affiliation(s)
- M Paidhungat
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032, USA
| | | | | |
Collapse
|
13
|
Abstract
Sporulation of a Bacillus subtilis strain (termed alpha(-) beta(-)) lacking the majority of the alpha/beta-type small, acid-soluble spore proteins (SASP) that are synthesized in the developing forespore and saturate spore DNA exhibited a number of differences from that of the wild-type strain, including delayed forespore accumulation of dipicolinic acid, overexpression of forespore-specific genes, and delayed expression of at least one mother cell-specific gene turned on late in sporulation, although genes turned on earlier in the mother cell were expressed normally in alpha(-) beta(-) strains. The sporulation defects in alpha(-) beta(-) strains were corrected by synthesis of chromosome-saturating levels of either of two wild-type, alpha/beta-type SASP but not by a mutant SASP that binds DNA poorly. Spores from alpha(-) beta(-) strains also exhibited less glutaraldehyde resistance and slower outgrowth than did wild-type spores, but at least some of these defects in alpha(-) beta(-) spores were abolished by the synthesis of normal levels of alpha/beta-type SASP. These results indicate that alpha/beta-type SASP may well have global effects on gene expression during sporulation and spore outgrowth.
Collapse
Affiliation(s)
- B Setlow
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032, USA.
| | | | | | | |
Collapse
|
14
|
Abstract
After a few minutes of germination, nucleoids in the great majority of spores of Bacillus subtilis and Bacillus megaterium were ring shaped. The major spore DNA binding proteins, the alpha/beta-type small, acid-soluble proteins (SASP), colocalized to these nucleoid rings early in spore germination, as did the B. megaterium homolog of the major B. subtilis chromosomal protein HBsu. The percentage of ring-shaped nucleoids was decreased in germinated spores with lower levels of alpha/beta-type SASP. As spore outgrowth proceeded, the ring-shaped nucleoids disappeared and the nucleoid became more compact. This change took place after degradation of most of the spores' pool of major alpha/beta-type SASP and was delayed when alpha/beta-type SASP degradation was delayed. Later in spore outgrowth, the shape of the nucleoid reverted to the diffuse lobular shape seen in growing cells.
Collapse
Affiliation(s)
- K Ragkousi
- Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032, USA
| | | | | | | |
Collapse
|
15
|
Pedersen LB, Ragkousi K, Cammett TJ, Melly E, Sekowska A, Schopick E, Murray T, Setlow P. Characterization of ywhE, which encodes a putative high-molecular-weight class A penicillin-binding protein in Bacillus subtilis. Gene 2000; 246:187-96. [PMID: 10767540 DOI: 10.1016/s0378-1119(00)00084-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The Bacillus subtilis genome sequencing project [Kunst et al., Nature 390 (1997) 249-256] identified ywhE as a gene that potentially encodes a high-molecular-weight class A penicillin-binding protein. Analysis of the expression of a translational ywhE-lacZ fusion showed that ywhE expression is sporulation-specific, and is controlled predominantly by the forespore-specific sigma factor sigma(F), and to a lesser extent by sigma(G). Primer extension analysis identified two transcription start sites located 26 and 27 nucleotides upstream of the ywhE translational initiation codon. Sequences located in the -10 and -35 regions relative to the transcription start sites showed good homology to the consensus sequences for promoter elements of sigma(F)-dependent genes. An insertional mutation in ywhE had no significant effect on growth, morphology, and sporulation, and ywhE spores had normal heat-resistance, cortex structure, and germination and outgrowth properties. However, overexpression of ywhE in Escherichia coli resulted in cell lysis.
Collapse
Affiliation(s)
- L B Pedersen
- Department of Biochemistry, University of Connecticut Health Center, Farmington, CT 06032, USA
| | | | | | | | | | | | | | | |
Collapse
|