Family With Sequence Similarity 50, Member A (FAM50A)

By screening a human skeletal muscle cDNA library with a cosmid fragment obtained from Xq28 by use of an enhanced promoter trap system, Toyoda et al. (1996) cloned a partial XAP5 cDNA, which they called HXC-26. The full-length cDNA encodes a deduced 339-amino acid soluble protein with a predicted molecular mass of approximately 40 kD. It contains 23% basic residues and an SV40 large T antigen nuclear localization signal. By Northern blot analysis, Mazzarella et al. (1997) detected a major 1.4-kb band in all tissues examined, with an additional 1.8-kb band detectable in some tissues. Expression was abundant in fetal brain, liver, and especially kidney, with little signal from the equivalent adult organs; expression was high in adult heart, skeletal muscle, spleen, thymus, prostate, and small intestine.