Cargando…
A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas
During fertilization in Chlamydomonas, gametes of opposite mating types interact with each other through sex-specific adhesion molecules on their flagellar surfaces. Flagellar adhesion brings the cell bodies of the gametes into close contact and initiates a signal transduction pathway in preparation...
Autores principales: | , , |
---|---|
Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
1998
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2175229/ https://www.ncbi.nlm.nih.gov/pubmed/9864368 |
_version_ | 1782145439859998720 |
---|---|
author | Kurvari, Venkatesh Grishin, Nick V. Snell, William J. |
author_facet | Kurvari, Venkatesh Grishin, Nick V. Snell, William J. |
author_sort | Kurvari, Venkatesh |
collection | PubMed |
description | During fertilization in Chlamydomonas, gametes of opposite mating types interact with each other through sex-specific adhesion molecules on their flagellar surfaces. Flagellar adhesion brings the cell bodies of the gametes into close contact and initiates a signal transduction pathway in preparation for cell–cell fusion. We have identified a cDNA, gsp1, whose transcript levels are upregulated during flagellar adhesion. The GSP1 polypeptide is a novel, gamete-specific homeodomain protein, the first to be identified in an alga. Its homeodomain shows significant identity with several higher plant homeodomain proteins. Although encoded by a single copy gene present in cells of both mating types, immunoblot analysis showed that GSP1 was expressed in mating type (mt)+ gametes, but was not detectable in mt− gametes or in vegetative cells of either mating type. Moreover, GSP1 appeared late during gametogenesis, suggesting that it may function during adhesion with mt− gametes or after zygote formation. GSP1 is expressed in imp11, mt− mutant gametes, which have a lesion in the mid gene involved in sex determination and exhibit many phenotypic characteristics of mt+ gametes. Thus, gsp1 is negatively regulated by mid and is the first molecule to be identified in Chlamydomonas that shows sex-limited expression. |
format | Text |
id | pubmed-2175229 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1998 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21752292008-05-01 A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas Kurvari, Venkatesh Grishin, Nick V. Snell, William J. J Cell Biol Regular Articles During fertilization in Chlamydomonas, gametes of opposite mating types interact with each other through sex-specific adhesion molecules on their flagellar surfaces. Flagellar adhesion brings the cell bodies of the gametes into close contact and initiates a signal transduction pathway in preparation for cell–cell fusion. We have identified a cDNA, gsp1, whose transcript levels are upregulated during flagellar adhesion. The GSP1 polypeptide is a novel, gamete-specific homeodomain protein, the first to be identified in an alga. Its homeodomain shows significant identity with several higher plant homeodomain proteins. Although encoded by a single copy gene present in cells of both mating types, immunoblot analysis showed that GSP1 was expressed in mating type (mt)+ gametes, but was not detectable in mt− gametes or in vegetative cells of either mating type. Moreover, GSP1 appeared late during gametogenesis, suggesting that it may function during adhesion with mt− gametes or after zygote formation. GSP1 is expressed in imp11, mt− mutant gametes, which have a lesion in the mid gene involved in sex determination and exhibit many phenotypic characteristics of mt+ gametes. Thus, gsp1 is negatively regulated by mid and is the first molecule to be identified in Chlamydomonas that shows sex-limited expression. The Rockefeller University Press 1998-12-28 /pmc/articles/PMC2175229/ /pubmed/9864368 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Regular Articles Kurvari, Venkatesh Grishin, Nick V. Snell, William J. A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas |
title | A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas
|
title_full | A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas
|
title_fullStr | A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas
|
title_full_unstemmed | A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas
|
title_short | A Gamete-specific, Sex-limited Homeodomain Protein in Chlamydomonas
|
title_sort | gamete-specific, sex-limited homeodomain protein in chlamydomonas |
topic | Regular Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2175229/ https://www.ncbi.nlm.nih.gov/pubmed/9864368 |
work_keys_str_mv | AT kurvarivenkatesh agametespecificsexlimitedhomeodomainproteininchlamydomonas AT grishinnickv agametespecificsexlimitedhomeodomainproteininchlamydomonas AT snellwilliamj agametespecificsexlimitedhomeodomainproteininchlamydomonas AT kurvarivenkatesh gametespecificsexlimitedhomeodomainproteininchlamydomonas AT grishinnickv gametespecificsexlimitedhomeodomainproteininchlamydomonas AT snellwilliamj gametespecificsexlimitedhomeodomainproteininchlamydomonas |