Recombinant Human SLITRK5 Protein, CF

SLITRK5 (Slit and Trk-like family member 5; also named LRR-containing protein 11) is a member of the SLITRK family of proteins (1, 2). This family currently includes six members, all of which contain a slit-like extracellular region and (save for SLITRK1) a Trk-like cytoplasmic region (3). Human SLITRK5 is a type I transmembrane (TM) protein that is 958 amino acids (aa) in length. It contains a putative 40 aa signal sequence, a 624 aa extracellular domain (ECD), a 21 aa TM segment, and a 273 aa cytoplasmic region. The ECD is characterized by the presence of two leucine-rich domains (LRD) that resemble those found in slit. Each LRD (aa 80 - 285 plus aa 384 - 579) contains seven and eight leucine-rich repeats (LRRs), respectively. The exact function of the LRRs is not known. Based on other LRRs, it might be assumed that they mediate protein-protein-interaction (4). The cytoplasmic region contains two conserved, potential phosphorylation sites at Tyr 833 and Tyr 917, plus a TrkA-like tyrosine phosphorylation site (YLxxL) at Tyr 945. SLITRK5 is expressed on embryonic neurons of the hippocampus (pyramidal layer) and thalamus (3). Based on SLITRK2 studies, SLITRK5 will block neurite extension (3). Human SLITRK5 shares 97% and 98% aa identity with mouse and canine SLITRK5, respectively.