Involved in early development of liver, exocrine pancreas and intestine, probably through cell cycle regulation. In liver, its function is partially redundant with leg1a function. Detected in all tissues tested, with the highest levels in serum (at protein level). At mRNA level, only expressed in liver. Expressed as early as 24 hours post fecondation (hpf), expressed at lower levels than leg1a. Morpholino knockdown of the protein causes a small liver phenotype. Morpholino which can simultaneously block the translation of leg1a and leg1b, causes a more severe small liver phenotype with hypoplastic exocrine pancreas and intestinal tube as well. Belongs to the LEG1 family.