OsA8 encodes a typical P-type ATPase-like protein of rice.
As a primary transporter, P-type H+-ATPases (P3A) mediate ATP-dependent H+ extrusion to the extracellular space, a process that generates pH and electrical potential difference across the PM , and this difference works as the motive force for a large set of secondary transporters, including symporter, antiporter, or uniporter, to drive their substrates against their concentration gradients.  Therefore, the H+-ATPase acts as a transducer: converting the chemical energy released from ATP hydrolysis into chemiosmotic energy.  The basic function of P-type H+-ATPases is the coupling ATP hydrolysis and H+-pumping. In general, the cells undergoing active metabolism have much higher activity of H+-ATPase than others. 
Expression pattern of OsA8 is investigated in rice seedlings. Transcripts of OsA8 accumulated more abundantly in roots than in leaves under normal growing condition. OsA8 expression is suppressed in both roots and leaves under N, P, and K deficiency, indicating a much broader role of it in nutrient acquisition in rice. 
Sequencing of the PCR products confirmed a single insertion of Tos17 in the OsA8 gene. Apart from this insertion, no other copies of Tos17 in the mutant were different from wild-type plants. Morphological comparison of the mutant and wild-type rice showed that, regardless of P supply, Osa8 mutants, in general, had smaller leaves, roots, and tillers. Consistent with these differences, biomass of both roots and shoots of the mutant plants is significantly smaller than that of wild-type plants. Notably, the biomass ratio of the root to the shoot in the mutant is significantly lower than that in the wild-type seedlings grown under P-starvation conditions. 
Among 10 OsA genes in rice, expression of OsA5, OsA9, and OsA10 is not detectable. Expression of OsA3 and OsA7 is relatively higher in both the OsA8 mutant and the wild-type seedlings. Knockout of OsA8 increased the expression of OsA1 and OsA2 in the roots of Pi-starved mutants. However, a lower abundance of OsA2 is noticed in leaves of the mutant. In addition, OsA6 appears to be induced only in roots of Pi-sufﬁcient wild-type plant. OsA4 seemed to express constitutively. This suggests a complex regulation of expression of the members of the OsA family in roots and leaves under Pi starvation conditions. It has been reported that two Pht1 genes, OsPT2 and OsPT6, were highly expressed in P-starved roots of the rice cultivar Nipponbare. In this study, the expression of these two genes is compared in wild-type and mutant plants derived from the rice cultivar Hitomebore. The expression of OsPT2 is detected in roots and leaves of the mutant and the wild type. P-starvation did not induce the expression of OsPT6 in roots of the mutant as compared with that of the wild type. In addition, knockout of OsA8did not noticeably affect the expression of other members of the Pht1 family. 
Labs working on this gene
State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China College of Agronomy, Hainan University, Danzhou, Hainan, 571737, China
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