Developmental expression of fermt genes (KIND) in Xenopus laevis.

Abstract

The Kindlin family represents a group of focal adhesion proteins that are comprised of three members, Kindlin-1, 2 and 3. Research into Kindlins has received much attention over the recent years, with studies pointing to the involvement of this family in the pathology of characterized diseases. Here, we describe the sequence alignment, gene expression and tissue localization of a fermt gene family - fermt1, 2 and 3 in Xenopus laevis embryos, which are the proposed orthologues of the mammalian Kindlin family. RT-PCR data showed early onset of fermt1 and 2 expression from stage 7 onwards; late onset of fermt3 from stage 20 onwards. Fermt proteins had a domain organization that was unique only to that of the Kindlin family, where the C-terminally located FERM domain was interspersed by pleckstrin homology (PH) domains. In-situ hybridization revealed fermt1 expression in the ectodermal and mesodermal tissues, especially in the lens and proctodeum; fermt2 in mesodermal tissues in particular the heart chamber and fermt3 in the ventral blood islands (VBI). Fermt genes showed overlapping expression domains with that of human and mouse KIND genes. From the data presented throughout this study, we therefore propose Xenopus laevis fermt genes to be the orthologues of human KIND genes.