Differential gene expression in the small intestines of wildtype and W/W-Vmice

Much of the evidence demonstrating the role of interstitial cells of Cajal (ICC) in pacemaking and neurotransmission in the gastrointestinal tract com es from studies of W/W-V mice. These animals have few pacemaker ICC in the small bowel due to reduced functional Kit protein. We examined gene express ion in the small intestines of wildtype and W/W-V mice. RNA expression in t he jejunums of wildtype and W/W-V mutants was studied using a differential gene expression method. Seven known genes were differentially expressed in wildtype and W/W-V mice. COX7B (cytochrome c oxidase, subunit VIIb) and SOR CIN (encoding multidrug-resistance complex, class 4) were suppressed in bot h fed and fasted W/W-V mice. Expression of another five genes was increased in W/W-V mice: ADA (adenosine deaminase), MDH1 (malate dehydrogenase), RPL -8 (ribosomal protein L8), SPTB2 (spectrin, nonerythroid, beta subunit), an d p6-5 (encoding phosphorylcholine [PC] T-cell suppressor factor [TsF]). Di fferential expression was the same in fasted and fed animals, suggesting th at the differences were independent of the dietetic stare. We conclude that several genes are differentially expressed in the small intestines of W/W- V mice where the major lesion is loss of pacemaker ICC. Differential gene d isplay may help develop a molecular profile of motility disorders in which ICC are lost.