absence of aquaporin-4 in skeletal muscle alters proteins involved in bioenergetic pathways and calcium handling没有aquaporin-4骨骼肌改变蛋白质参与生物能量学途径和钙处理.pdfVIP

Absence of Aquaporin-4 in Skeletal Muscle Alters Proteins Involved in Bioenergetic Pathways and Calcium Handling 1,2 1,2 3 3 1,2 Davide Basco , Grazia Paola Nicchia , Angelo D’Alessandro , Lello Zolla , Maria Svelto , Antonio Frigeri1,2* 1 Department of General and Environmental Physiology, University of Bari-Aldo Moro, Bari, Italy, 2 Centre of Excellence in Comparative Genomics (CEGBA), University of ` Bari-Aldo Moro, Bari, Italy, 3 Department of Environmental Sciences, Tuscia University, Largo dell’Universita snc, Viterbo, Italy Abstract Aquaporin-4 (AQP4) is a water channel expressed at the sarcolemma of fast-twitch skeletal muscle fibers, whose expression is altered in several forms of muscular dystrophies. However, little is known concerning the physiological role of AQP4 in skeletal muscle and its functional and structural interaction with skeletal muscle proteome. Using AQP4-null mice, we analyzed the effect of the absence of AQP4 on the morphology and protein composition of sarcolemma as well as on the whole skeletal muscle proteome. Immunofluorescence analysis showed that the absence of AQP4 did not perturb the expression and cellular localization of the dystrophin-glycoprotein complex proteins, aside from those belonging to the extracellular matrix, and no alteration was found in sarcolemma integrity by dye extravasation assay. With the use of a 2DE- approach (BN/SDS), protein maps revealed that in quadriceps, out of 300 Coomassie-blue detected and matched spots, 19 proteins exhibited changed expression in AQP42/ 2 compared to WT mice. In pa