Genomic Structure and Chromosomal Mapping of the Mouse STOP Gene (Mtap6)

Abstract The microtubule associated protein STOP (Stable Tubule Only Polypeptide) is a calmodulin-regulated protein able to induce a high degree of microtubule stability. STOP is abundant in neurons which contain large subpopulations of stable microtubules. Genomic clones spanning 67 kb and encompassing the mouse STOP gene ( Mtap6 ) have been isolated and characterized. These clones derive from a single gene mapping to the E2-F1 region of mouse chromosome 7. The gene is composed of 4 exons that exhibit conventional vertebrate splicing sequences. Transcription of the gene initiate at multiple sites in a 85 nucleotide region located 530 bases upstream the translation initiation codon. Accordingly, the 5′ flanking region of the gene lacks a TATA box or an initiator element at usual position. The protein encoded by the mouse STOP gene ( Mtap6 ) is composed of 906 amino acids and presents a 91 % identities with the rat brain STOP.