Expression of a linker histone-like gene in the primordial germ cells in zebrafish

Similar to many other organisms, specification of primordial germ cells (PGCs) in zebrafish occurs during early development and depends on inheritance of 'germ plasm' determinants. Following their specification, the PGCs exhibit characteristic transcriptional profile and cell behaviour. Here we describe the cloning, expression pattern and sub-cellular localization of the zebrafish H1 type linker histone, H1M, which is specifically expressed in the PGCs in the second phase of their development. H1M transcripts are uniformly distributed during blastula stages, but become restricted to the PGCs during gastrulation and remain visible in PGCs as they migrate towards the region of the gonad.