POU-DOMAIN GENE-EXPRESSION IN THE GASTROINTESTINAL-TRACT

The process of self-renewal which occurs in the gastrointestinal epith elium is greatly amplified and accelerated during the intestinal adapt ation which occurs in the residual ileum after massive small bowel res ection (MSBR). As with growth and development, these processes must in volve the coordinated regulation of many genes. Several families of nu clear proteins are known to be involved in the control of gene express ion during development including the POU-domain genes; their expressio n has not been characterized in the gastrointestinal tract during norm al cellular renewal or adaptation, and POU-domain encoding cDNAs were cloned from ileal RNA. Three known genes were cloned: Oct-1, Brn-1 and Tst-1 but no novel members of this gene family were identified The en coded sequence for rat Oct-1 differs from that previously reported. Oc t-1 is relatively ubiquitously expressed with increased expression dur ing both development and adaptation. Minimal expression of Tst-1 was o bserved. Brn-1 exhibits limited expression in the adult gastrointestin al tract but may play a role in the fetal gastrointestinal tract. (C) 1995 Wiley-Liss, Inc.