Linkage assignments of the porcine ATP1A2, ATP1B1 and V-ATPase (CGI-11) genes to chromosome 4

Na+, K+-ATPase (EC 3.6.1.37) is a membrane-bound enzyme responsible for the ATP-dependent counter transport of sodium and potassium ions across the plasma cell membrane. The molecule is composed of two subunits: a catalytic alpha subunit and a regulatory beta subunit. A gene for subunit alpha, ATP1A2, and a gene for subunit beta, ATP1B1, have been physically assigned to porcine chromosome 4. The vacuolar H+-ATPase (ATP6; V-AT Pase; EC 3.6.1.34) is a multisubunit enzyme that translocates protons into intracellular organelles or across the plasma membrane of specialized cells against an electrochemical gradient. The gene for porcine 54- and 56-kDa V-ATPase subunit isoforms (V-ATPase or CGI-11, according to the temporary human nomenclature) was assigned to chromosome 4q1.4-q1.6. As these three genes are located on porcine chromosome 4, where QTLs for growth and carcass traits have been found, we integrated these loci into a more detailed linkage map by means of SSCP or PCR-RFLP analyses.