High impact information on PPP1R12B

• Characterization of cardiac MYPT2 (an isoform of the smooth muscle phosphatase [MP] target subunit, MYPT1) is described [1].
• Adenovirus-mediated gene transfer of MYPT2 and PP1cdelta reduced the phosphorylation level of cardiac light chains following stimulation with A23187 [1].
• Overexpression of MYPT2 and PP1cdelta blocked the angiotensin II-induced sarcomere organization in cultured cardiomyocytes [1].
• MYPT2 activated PP1cdelta activity, using light chains from smooth and cardiac muscle, by reducing K(m) and increasing k(cat) [1].
• MYPT2 gene is transcribed abundantly in heart and skeletal muscle, while Western blots using an antibody specific for MYPT2 showed exclusive expression of MYPT2 in heart and brain [2].

Biological context of PPP1R12B

• Overall, the deduced amino acid sequence of MYPT2 was 61% identical to MYPT1 [2].
• A recombinant of the N-terminal two-thirds of MYPT2 bound to the catalytic subunit of type 1 phosphatase (delta isoform) and increased activity toward phosphorylated myosin light chain [2].
• In situ hybridization localized the human MYPT2 gene on chromosome 1q32.1, compared to the chromosomal location 12q15-q21-2 for MYPT1 [2].
• Here we have cloned a novel isoform of MYPT1, termed MYPT2, from a human brain cDNA library screened with a cDNA fragment of rat MYPT1 [2].

References