Kelch Like Protein 3 (KLHL3)

KLHL3a encodes the deduced full-length protein of 587 amino acids, whereas KLHL3b encodes a 555-amino acid protein and KLHL3c encodes a 505-amino acid protein. Instead of generating proteins with unique N-terminal sequences, alternative usage of the promoters affects only the translation initiation site used. The KLHL3 protein shares 77% sequence similarity with Drosophila kelch and 89% similarity with human KLHL2. Like kelch and KLHL2, KLHL3 contains a poxvirus and zinc finger (POZ) domain in the N terminus and 6 tandem repeats (kelch repeats) in the C terminus. Northern blot analysis detected expression of a 6.5-kb mRNA in fetal liver, thymus, and lymph node; the transcript was barely detectable in spleen and appeared to be absent in peripheral blood and bone marrow.