Downregulation of OsSPX1 Causes Semi-Male Sterility and Grain Yield Reduction in Rice

OsSPX1, a rice gene involved in phosphate (Pi)-sensing mechanism plays an essential role in the Pi-signalling network through interaction with OsPHR2. Kang Zhang and researchers from China Agricultural University studied the potential function of OsSPX1 during rice reproductive phase.

Using antisense and sense transgenic rice lines, researchers discovered that downregulation of OsSPX1 caused reduction of seed-setting rate and filled grain number. Further examination of anthers and pollens of the transgenic and wild-type plants found that the antisense of OsSPX1 gene led to semi-male sterility, lacking mature pollen grains and phenotypes with a disordered surface of anthers and pollens.

Further genome analysis revealed that downregulation of OsSPX1 significantly affected expression of genes involved in important processes including carbohydrate metabolism, sugar transport and anther development leading to semi-male sterility and in turn low seed-set. These genes may have been related to pollen fertility and male gametophyte development.

For more information, read the full article on Plant Biotechnology Journal.