SEGMENT-SPECIFIC EXPRESSION OF THE GAP JUNCTION GENE CONNEXIN31 DURING HINDBRAIN DEVELOPMENT

During segmentation of the mouse hindbrain (d8.0-8.5 pc), expression o f the gap junction gene connexin31 (cx31) is precisely restricted to r hombomeres (r) 3 and 5. Shortly afterwards, during the turning, proces s, cx31 expression in rhombomere 3 decreases and is no longer detectab le at d9.5 pc, whereas expression in rhombomere 5 is maintained until about d10.0 pc. So far, cx31 is the first gap junction gene found to b e expressed in rhombomeres. Its precise segmental and temporal express ion pattern may reflect a critical requirement of cx31 channels for th ese odd numbered rhombomeres to acquire distinct cell identities.