MTCP1 is part of a bicistronic locus that also includes the CMC4 gene . The MTCP1 gene consists of at least seven exons and exhibits complex alternative splicing . The gene produces two distinct transcripts: one encoding the p13 MTCP1 protein and the other encoding the p8 MTCP1 protein . The p13 MTCP1 protein is 107 amino acids long and shares 39% identity with the TCL1 protein .
The exact function of p13 MTCP1 is not fully understood, but it is known to be involved in the oncogenesis of T-PLL . Overexpression of p13 MTCP1 is considered critical in the development of this leukemia . The protein is weakly expressed in leukemia cells bearing the t(X;14) translocation but not in other leukemia cells or normal lymphocytes .