Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.

Mitosis and meiosis have two mechanisms for regulating the accuracy of chromosome segregation: error correction and the spindle assembly checkpoint (SAC). We have investigated the function of several checkpoint proteins in meiosis I of Drosophila oocytes. Increased localization of several SAC protei...

Full description

Saved in:
Bibliographic Details
Main Authors: Joanatta G Shapiro, Neha Changela, Janet K Jang, Jay N Joshi, Kim S McKim
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2025-01-01
Series:PLoS Genetics
Online Access:https://doi.org/10.1371/journal.pgen.1011400
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850145057283244032
author Joanatta G Shapiro
Neha Changela
Janet K Jang
Jay N Joshi
Kim S McKim
author_facet Joanatta G Shapiro
Neha Changela
Janet K Jang
Jay N Joshi
Kim S McKim
author_sort Joanatta G Shapiro
collection DOAJ
description Mitosis and meiosis have two mechanisms for regulating the accuracy of chromosome segregation: error correction and the spindle assembly checkpoint (SAC). We have investigated the function of several checkpoint proteins in meiosis I of Drosophila oocytes. Increased localization of several SAC proteins was found upon depolymerization of microtubules by colchicine. However, unattached kinetochores or errors in biorientation of homologous chromosomes do not induce increased SAC protein localization. Furthermore, the metaphase I arrest does not depend on SAC genes, suggesting the APC is inhibited even if the SAC is not functional. Two SAC proteins, ROD of the ROD-ZW10-Zwilch (RZZ) complex and MPS1, are also required for the biorientation of homologous chromosomes during meiosis I, suggesting an error correction function. Both proteins aid in preventing or correcting erroneous attachments and depend on SPC105R for localization to the kinetochore. We have defined a region of SPC105R, amino acids 123-473, that is required for ROD localization and biorientation of homologous chromosomes at meiosis I. Surprisingly, ROD removal from kinetochores and movement towards spindle poles, termed "streaming," is independent of the dynein adaptor Spindly and is not linked to the stabilization of end-on attachments. Instead, meiotic RZZ streaming appears to depend on cell cycle stage and may be regulated independently of kinetochore attachment or biorientation status. We also show that Spindly is required for biorientation at meiosis I, and surprisingly, the direction of RZZ streaming.
format Article
id doaj-art-8c1e1dbd4e33437a8e095d10fa1e447a
institution OA Journals
issn 1553-7390
1553-7404
language English
publishDate 2025-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Genetics
spelling doaj-art-8c1e1dbd4e33437a8e095d10fa1e447a2025-08-20T02:28:11ZengPublic Library of Science (PLoS)PLoS Genetics1553-73901553-74042025-01-01211e101140010.1371/journal.pgen.1011400Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.Joanatta G ShapiroNeha ChangelaJanet K JangJay N JoshiKim S McKimMitosis and meiosis have two mechanisms for regulating the accuracy of chromosome segregation: error correction and the spindle assembly checkpoint (SAC). We have investigated the function of several checkpoint proteins in meiosis I of Drosophila oocytes. Increased localization of several SAC proteins was found upon depolymerization of microtubules by colchicine. However, unattached kinetochores or errors in biorientation of homologous chromosomes do not induce increased SAC protein localization. Furthermore, the metaphase I arrest does not depend on SAC genes, suggesting the APC is inhibited even if the SAC is not functional. Two SAC proteins, ROD of the ROD-ZW10-Zwilch (RZZ) complex and MPS1, are also required for the biorientation of homologous chromosomes during meiosis I, suggesting an error correction function. Both proteins aid in preventing or correcting erroneous attachments and depend on SPC105R for localization to the kinetochore. We have defined a region of SPC105R, amino acids 123-473, that is required for ROD localization and biorientation of homologous chromosomes at meiosis I. Surprisingly, ROD removal from kinetochores and movement towards spindle poles, termed "streaming," is independent of the dynein adaptor Spindly and is not linked to the stabilization of end-on attachments. Instead, meiotic RZZ streaming appears to depend on cell cycle stage and may be regulated independently of kinetochore attachment or biorientation status. We also show that Spindly is required for biorientation at meiosis I, and surprisingly, the direction of RZZ streaming.https://doi.org/10.1371/journal.pgen.1011400
spellingShingle Joanatta G Shapiro
Neha Changela
Janet K Jang
Jay N Joshi
Kim S McKim
Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.
PLoS Genetics
title Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.
title_full Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.
title_fullStr Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.
title_full_unstemmed Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.
title_short Distinct checkpoint and homolog biorientation pathways regulate meiosis I in Drosophila oocytes.
title_sort distinct checkpoint and homolog biorientation pathways regulate meiosis i in drosophila oocytes
url https://doi.org/10.1371/journal.pgen.1011400
work_keys_str_mv AT joanattagshapiro distinctcheckpointandhomologbiorientationpathwaysregulatemeiosisiindrosophilaoocytes
AT nehachangela distinctcheckpointandhomologbiorientationpathwaysregulatemeiosisiindrosophilaoocytes
AT janetkjang distinctcheckpointandhomologbiorientationpathwaysregulatemeiosisiindrosophilaoocytes
AT jaynjoshi distinctcheckpointandhomologbiorientationpathwaysregulatemeiosisiindrosophilaoocytes
AT kimsmckim distinctcheckpointandhomologbiorientationpathwaysregulatemeiosisiindrosophilaoocytes