XCS-1, a maternally expressed gene product involved in regulating mitosis in Xenopus.
نویسندگان
چکیده
The regulation of the cell cycle during early development is an important and complex biological process. We have cloned a cDNA, XCS-1, that may play an important role in regulating mitosis during early embryogenesis in Xenopus laevis. XCS-1 is a maternally expressed gene product that is the Xenopus homologue of the human cleavage signal protein (CS-1). XCS-1 transcripts were detected in oocytes with the titer decreasing just prior to the MBT. During development the XCS-1 protein was detected on the membrane and in the nucleus of blastomeres. It was also detected on the mitotic spindle in mitotic cells and on the centrosomes in interphase cells. Overexpression of myc-XCS-1 in Xenopus embryos resulted in abnormal mitoses with increased numbers of centrosomes, multipolar spindles, and abnormal distribution of chromosomes. Also, we observed incomplete cytokinesis resulting in multiple nuclei residing in the same cytoplasm with the daughter nuclei in different phases of the cell cycle. The phenotype depended on the presence of the N terminus of XCS-1 (aa 1-73) and a consensus NIMA kinase phosphorylation site (aa159-167). Mutations in this site affected the ability of the overexpressed XCS-1 protein to produce the phenotype. These results suggest that XCS-1 is a maternal factor playing an important role in the regulation of the cell cycle during early embryogenesis and that its function depends on its state of phosphorylation.
منابع مشابه
Expression of hsp90 Alpha and hsp90 Beta during Xenopus laevis Embryonic Development
Background: Members of the eukaryotic Hsp90 family function as important molecular chaperones in the assembly, folding and activation of cellular signaling in development. Two hsp90 genes, hsp90 alpha and hsp90 beta, have been identified in fish and homeothermic vertebrates but not in poikilothermic vertebrates. In the present study, the expression of hsp90 alpha and hsp90 beta genes in Xenopus...
متن کاملZFPIP/Zfp462 is maternally required for proper early Xenopus laevis development.
ZFPIP (Zinc Finger Pbx1 Interacting Protein) has been recently identified in our laboratory in a yeast two hybrid screen using an embryonic mouse cDNA library and PBX1 as a bait. This gene encodes a large protein (250 kDa) that contains a bipartite NLS, numerous C2H2 zinc fingers and is highly conserved amongst vertebrates. In order to address the role of ZFPIP during embryonic development, we ...
متن کاملA novel TBP-interacting zinc finger protein functions in early development of Xenopus laevis.
A zinc finger protein that interacts with Xenopus TATA-binding protein was previously isolated by a yeast two-hybrid screen and found to serve as a transcriptional repressor. The gene was designated the negatively regulating zinc finger protein gene (NZFP). Herein, NZFP was found to be expressed maternally. After gastrulation, the level of NZFP mRNA decreased significantly throughout the neurul...
متن کاملDarmin is a novel secreted protein expressed during endoderm development in Xenopus.
Endoderm development is an area of intense interest in developmental biology, but progress has been hampered by the lack of specific markers for differentiated endodermal cells. In an unbiased secretion cloning screen of Xenopus gastrula embryos we isolated a novel gene, designated Darmin. Darmin encodes a secreted protein of 56 kDa containing a peptidase M20 domain characteristic of the glutam...
متن کاملPlx1 is required for chromosomal DNA replication under stressful conditions
Polo-like kinase (Plk)1 is required for mitosis progression. However, although Plk1 is expressed throughout the cell cycle, its function during S-phase is unknown. Using Xenopus laevis egg extracts, we demonstrate that Plx1, the Xenopus orthologue of Plk1, is required for DNA replication in the presence of stalled replication forks induced by aphidicolin, etoposide or reduced levels of DNA-boun...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of cell science
دوره 113 ( Pt 13) شماره
صفحات -
تاریخ انتشار 2000