title: Ontogeny of plasma membrane Ca2+ ATPase isoforms in the neural retina of the postnatal rat.
abstract: Calcium ion (Ca(2+)) signaling has been widely implicated in developmental events in the retina, but little is known about the specific mechanisms utilized by developing neurons to decrease intracellular Ca(2+). Using immunocytochemistry, we determined the expression profiles of all known isoforms of a key Ca(2+) transporter, the plasma membrane Ca(2+) ATPase (PMCA), in the rat retina. During the first postnatal week, the four PMCA isoforms were expressed in patterns that differed from their expression in the adult retina. At birth, PMCA1 was found in the ventricular zone and nascent cell processes in the distal retina as well as in ganglion and amacrine cells. After the first postnatal week, PMCA1 became restricted to photoreceptors and cone bipolar cells. By P10 (by postnatal day 10), most inner retinal PMCA consisted of PMCA2 and PMCA3. Prominent PMCA4 expression appeared after the first postnatal week and was confined primarily to the ON sublamina of the inner plexiform layer (IPL). The four PMCA isoforms could play distinct functional roles in the development of the mammalian retina even before synaptic circuits are established. Their expression patterns are consistent with the hypothesis that inner and outer retinal neurons have different Ca(2+) handling needs.
authors.affiliation: Department of Ophthalmology, University of California, San Francisco, 94143, USA.
authors.forename: René C
authors.initials: RC
authors.lastname: Rentería
authors.forename: Emanuel E
authors.initials: EE
authors.lastname: Strehler
authors.forename: David R
authors.initials: DR
authors.lastname: Copenhagen
authors.forename: David
authors.initials: D
authors.lastname: Krizaj
mesh_terms: D000367:Age Factors; D026905:Amino Acid Transport Systems / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D000252:Calcium-Transporting ATPases / Q000145:classification / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000145:classification / Q000378:metabolism*; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D003952:Diagnostic Imaging / Q000379:methods; D005968:Glutamate Decarboxylase / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods; D007527:Isoenzymes / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000201:enzymology*; D053499:Plasma Membrane Calcium-Transporting ATPases; D051381:Rats; D020318:Rats, Long-Evans; D012160:Retina / Q000166:cytology* / Q000254:growth & development*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; D033921:Vesicular Transport Proteins / Q000378:metabolism
chemical_list: D026905:Amino Acid Transport Systems; D027682:Cation Transport Proteins; D007527:Isoenzymes; D009419:Nerve Tissue Proteins; C079052:SVP-38 protein, rat; C118623:Slc32a1 protein, rat; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; D033921:Vesicular Transport Proteins; D014446:Tyrosine 3-Monooxygenase; D002795:Choline O-Acetyltransferase; D053499:Plasma Membrane Calcium-Transporting ATPases; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2; C506955:Atp2b1 protein, rat; D000252:Calcium-Transporting ATPases