Over-expression of the rice LRK1 gene improves quantitative yield components

Plant Biotechnol J. 2009 Sep;7(7):611-20. doi: 10.1111/j.1467-7652.2009.00428.x. Epub 2009 Jul 10.

Abstract

In rice (Oryza sativa L.), the number of panicles, spikelets per panicle and grain weight are important components of grain yield. These characteristics are controlled by quantitative trait loci (QTLs) and are derived from variation inherent in crops. As a result of the complex genetic basis of these traits, only a few genes involved in their control have been cloned and characterized. We have previously map-cloned a gene cluster including eight leucine-rich repeat receptor-like kinase (LRK) genes in Dongxiang wild rice (Oryza rufipogon Griff.), which increased the grain yield by 16%. In the present study, we characterized the LRK1 gene, which was contained in the donor parent (Dongxiang wild rice) genome and absent from the recurrent parent genome (Guichao2, Oryza sativa L. ssp. indica). Our data showed that rice LRK1 is a plasma membrane protein expressed constitutively in leaves, young panicles, roots and culms. The over-expression of rice LRK1 results in increased panicles, spikelets per panicle, weight per grain and enhanced cellular proliferation, leading to a 27.09% increase in total grain yield per plant. The increased number of panicles and spikelets per panicle are associated with increased branch number. Our data suggest that rice LRK1 regulates rice branch number by enhancing cellular proliferation. The functional characterization of rice LRK1 facilitates an understanding of the mechanisms involved in cereal crop yield, and may have utility in improving grain yield in cereal crops.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Southern
  • Cell Proliferation
  • Gene Expression*
  • Genome, Plant
  • Membrane Proteins / genetics
  • Membrane Proteins / physiology*
  • Oryza / genetics
  • Oryza / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / physiology*
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism*
  • Proteins / genetics
  • Proteins / physiology*
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Membrane Proteins
  • Plant Proteins
  • Proteins
  • leucine-rich repeat proteins