Rice ACID PHOSPHATASE 1 regulates Pi stress adaptation by maintaining intracellular Pi homeostasis

Abstract

The concentration and homeostasis of intracellular phosphate (Pi) are crucial for sustaining cell metabolism and growth. During short‐term Pi starvation, intracellular Pi is maintained relatively constant at the expense of vacuolar Pi. After the vacuolar stored Pi is exhausted, the plant cells induce the synthesis of intracellular acid phosphatase (APase) to recycle Pi from expendable organic phosphate (Po). In this study, the expression, enzymatic activity and subcellular localization of ACID PHOSPHATASE 1 (OsACP1) were determined. OsACP1 expression is specifically induced in almost all cell types of leaves and roots under Pi stress conditions. OsACP1 encodes an acid phosphatase with broad Po substrates and localizes in the endoplasmic reticulum (ER) and Golgi apparatus (GA). The phylogenic analysis demonstrates that OsACP1 has a similar structure with human acid phosphatase PHOSPHO1. Overexpression or mutation of OsACP1 affected Po degradation and utilization, which further influenced plant growth and productivity under both Pi‐sufficient and Pi‐deficient conditions. Moreover, overexpression of OsACP1 significantly affected intracellular Pi homeostasis and Pi starvation signalling. We concluded that OsACP1 is an active acid phosphatase that regulates rice growth under Pi stress conditions by recycling Pi from Po in the ER and GA.

Comparative physiological and transcriptomic analysis of two salt-tolerant soybean germplasms response to low phosphorus stress: role of phosphorus uptake and antioxidant capacity

“…In response to P deficiency, plants evolved a series of intelligent adaptive mechanisms to improve P availability and increase its uptake efficiency, one of which was the production and secretion of acid phosphatase (ACP) [ 39 , 40 ]. The increased expression and activity of ACP could improve the absorption and utilization efficiency of P [ 41 ]. Our study showed that A74 had higher P accumulation, P uptake efficiency, and ACP activity under both LP and LPS stress than A6 (Fig.…”

Increased PHOSPHO1 expression mediates cortical bone mineral density in renal osteodystrophy

“…It is unknown if such a Pi negative feedback mechanism controls PHOSPHO1 expression, but the increased osteoclast resorption observed in ROD will bring about the release of Pi which will contribute to the observed hyperphosphatemia and impede the skeleton from exerting its normal reservoir function when serum Pi concentrations increase ( Hruska et al 2008 ). In such a scenario, the resulting Pi stress conditions experienced by the skeleton may drive higher PHOSPHO1 expression in a similar way to the LePS2 protein and other phosphatases such as OsACP1 a PHOSPHO1-like acid phosphatase in rice ( Deng et al 2022 ).…”

Genome wide association studies for acid phosphatase activity at varying phosphorous levels in Brassica juncea L

“…Overexpression of PAP10 (that shows both SAP and IAP properties) in Arabidopsis and rice have been found to significantly increase the plant’s ability to degrade Po and tolerance to low Pi stress ( Wang et al., 2011 ; Deng et al., 2020 ). PNP and AT5G51260 regulate Pi tolerance by releasing Pi during polynucleotide synthesis from nucleotide diphosphates or triphosphates ( Marchive et al., 2010 ; Deng et al., 2021 ). We also predicted several genes with roles in phytohormone and sugar signalling pathways and root modulation.…”