Du-1

1.Discovery and Positioning With eight low amylose content mutants and normal hybrid rice varieties, analysis the amylose content of F1 and F2 seeds, found that the low amylose content of the mutant controlled by recessive single gene, the gene loci were found to have 5, respectively named du - 1, du - 2, du - 3, and du du - 4-5. These sites with ranged wx, have additive effect, among them, the du - 1 in rice chromosome 7, du - 4 location on chromosome 4. 2.Biological Function of Genes

   Du-1 and Du-2 may encode a protein splicing factor, similar to the SR protein by splicing with Wxb precursor mRNA may enhance the son, and two hidden in Wxb gene splicing sites to form stable complex, thus guide Wxb precursor mRNA splicing. Du-1 and Du-2, on the other hand, failure to form a normal protein splicing factor, make Wxb precursor mRNA splicing process normally affected by certain, resulting in a loss of mutant amylose contents, but after the splicing transcription regulation is no effect. Also found and du-1 and du-2 does not affect the normal Wxa precursor mRNA splicing.
   Du-1 and Du-2 has a different effect on endosperm and pollen. Although these two mutations in endosperm Wxb transcription product have similar shear effect, but in the mutant pollen Wxb du - 1 mRNA levels compared with endosperm drop more, while du - 2 mutant in the two groups of Wxb mRNA levels. Therefore, rice and du-1 and du-2 loci coding regulation of tissue specificity of shear factor, thus to selective precursor mRNA shear.

References 1. Masayuki Isshiki;Midori Nakajima;Hikaru Satoh and Ko Shimamoto

 dull: rice mutants with tissue-specific effects on the splicing of the waxy pre-mRNA
 The Plant Journal, 2000, 23(4): 451-460

2. M. Yano;K. Okuno;H. Satoh and T. Omura

 Chromosomal location of genes conditioning low amylose content of endosperm starches in rice, Oryza sativa L.
 Theoretical and Applied Genetics, 1988, 76(2): 183-189

3. Hikaru Satoh;Takeshi Omura

 New Endosperm Mutations Induced by Chemical Mutagens in Rice Oryza sativa L.
 Japanese Journal of Breeding, 1981, 31(3): 316-326