Rice OsHKT2;1 transporter mediates large Na+ influx component into K+-starved roots for growth.

ABSTRACT: Excessive accumulation of sodium in plants causes toxicity. No mutation that greatly diminishes sodium (Na+) influx into plant roots has been isolated. The OsHKT2;1 (previously named OsHKT1) transporter from rice functions as a relatively Na+-selective transporter in heterologous expression systems, but the in vivo function of OsHKT2;1 remains unknown. Here, we analyzed transposon-insertion rice lines disrupted in OsHKT2;1. Interestingly, three independent oshkt2;1-null alleles exhibited significantly reduced growth compared with wild-type plants under low Na+ and K+ starvation conditions. The mutant alleles accumulated less Na+, but not less K+, in roots and shoots. OsHKT2;1 was mainly expressed in the cortex and endodermis of roots. (22)Na+ tracer influx experiments revealed that Na+ inf

SUBMITTER: Horie T 

PROVIDER: S-EPMC1894770 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature