Expression and tissue distribution of human X-linked armadillo repeat containing-6.

The armadillo family of proteins has been implicated in embryogenesis and tumorigenesis. Armadillo repeat containing X-linked (ARMCX)1-6 and its most closely related protein, ARMC10, share an uncharacterized domain in their carboxyl-terminal region and thereby constitute a unique subfamily. We previously detected an elevated ARMCX6 mRNA level in human cervical carcinoma (HeLa) cells in which the cyclin-dependent kinase inhibitor 2A products (p16INK4A and p14ARF) were silenced by RNA interference; however, the function of the ARMCX6 gene has yet to be determined. In the present study, we demonstrated that ARMCX6 tagged with green fluorescent protein was localized in the cytoplasm of HeLa cells. ARMCX6 mRNA was highly detected in the pancreas and spleen, indicating a tissue-specific expression pattern in human tissues. Taken together, these results suggest that ARMCX6 may be uniquely involved in a specific cellular function of certain tissues.