Analysis of gene-disruption mutants of a sucrose phosphate synthase gene in rice, OsSPS1, shows the importance of sucrose synthesis in pollen germination

Plant Sci. 2014 Aug:225:102-6. doi: 10.1016/j.plantsci.2014.05.018. Epub 2014 Jun 2.

Abstract

The molecular function of an isoform of sucrose phosphate synthase (SPS) in rice, OsSPS1, was investigated using gene-disruption mutant lines generated by retrotransposon insertion. The progeny of the heterozygote of disrupted OsSPS1 (SPS1(+/-)) segregated into SPS1(+/+), SPS1(+/-), and SPS1(-/-) at a ratio of 1:1:0. This distorted segregation ratio, together with the expression of OsSPS1 in the developing pollen revealed by quantitative RT-PCR analysis and promoter-beta-glucuronidase (GUS) fusion assay, suggested that the disruption of OsSPS1 results in sterile pollen. This hypothesis was reinforced by reciprocal crosses of SPS1(+/-) plants with wild-type plants in which the disrupted OsSPS1 was not paternally transmitted to the progeny. While the pollen grains of SPS(+/-) plants normally accumulated starch during their development, pollen germination on the artificial media was reduced to half of that observed in the wild-type control. Overall, our data suggests that sucrose synthesis via OsSPS1 is essential in pollen germination in rice.

Keywords: Oryza sativa L; Pollen germination; Pollen maturation; Sucrose phosphate synthase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Crosses, Genetic
  • Genes, Plant*
  • Glucosyltransferases / genetics*
  • Glucosyltransferases / metabolism
  • Heterozygote
  • Mutation*
  • Oryza / enzymology
  • Oryza / genetics*
  • Oryza / metabolism
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Pollen / metabolism*
  • Retroelements
  • Starch / metabolism
  • Sucrose / metabolism*

Substances

  • Plant Proteins
  • Retroelements
  • Sucrose
  • Starch
  • Glucosyltransferases
  • sucrose-phosphate synthase