Murine cDNA encoding a novel type I HSP40/DNAJ homolog, mmDjA4(1)

We have cloned a cDNA encoding a novel type I HSP40/DNAJ protein from the mouse EST database, and designated it mmDjA4 (Mus musculus type I DnaJ homolog 4). This cDNA encodes 397 amino acid residues whose sequence shows 67 and 51% identity with the previously identified murine Hsj2 and mDj3, respectively. The sequence of mmDjA4 contains the four repeats of CxxCxGxG motif which are characteristic of type I HSP40/DNAJ proteins, and a CaaX prenylation motif at the carboxy terminus. Northern blot analysis showed that mmDjA4 is specifically expressed in mouse testis and heart. This is the fourth member of the mammalian type I HSP40/DNAJ family to be identified.