Embryonic expression patterns of the mouse and chick Gas1 genes

Control of cell proliferation is essential to generate the defined form of a multi-cellular organism. While much is known about the regulators for cel l cycle progression, relatively little is known about the start of growth a rrest. Growth arrest (GO) is defined as a cell in a metabolically active bu t proliferation-quiescent state (reviewed in Baserga (1985) The Biology of Cell Reproduction), typically induced by serum starvation in vitro. Using s ubtractive hybridization, Schneider et al. (Cell 54 (1988) 787) identified six genes (Gas1 through Gas6) whose expressions are upregulated in serum-de prived NIH3T3 cells. Among the Gas genes. Gas1 is the only one that can cau se growth arrest when expressed in cultured cell (Cell 70 (1995) 595: int. J. Cancer 9 (1998, 569). Here, we describe for the first time the expressio n pattern of Gas1 during mouse embryogenesis. Our data reveal that Gas1 is expressed in many regions that the cells are actively proliferating and sug gest that it may have other roles during development than negatively regula ting cell proliferation. Furthermore, we have cloned the chick GAS1 gene an d documented the similarity and divergence of Gas1 gene expression patterns between the two species. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.