Inositol polyphosphate 4-phosphatase type I regulates cell growth downstream of transcription factor GATA-1
AUTOR(ES)
Vyas, Paresh
FONTE
The National Academy of Sciences
RESUMO
Megakaryocytes lacking transcription factor GATA-1 fail to complete maturation in vivo and hyperproliferate. To define how GATA-1 regulates megakaryocyte cell growth we searched for mRNA transcripts expressed in primary wild-type, but not GATA-1−, megakaryocytes. One differentially expressed transcript encodes inositol polyphosphate 4-phosphatase type I (4-Ptase I). This enzyme hydrolyses phosphatidylinositol 3,4-bisphosphate and also has lesser activity against soluble analogues of this lipid, inositol 3,4-bisphosphate and inositol 1,3,4-triphosphate. Reintroduction of 4-Ptase I into both primary GATA-1− and wild-type megakaryocytes significantly retards cell growth, suggesting that absence of 4-Ptase I may contribute to the hyperproliferative phenotype of GATA-1− megakaryocytes. Overexpression of 4-Ptase I also markedly reduces growth of NIH 3T3 fibroblasts. Taken together, these data indicate that 4-Ptase I is a regulator of cell proliferation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=17638Documentos Relacionados
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