Phenotypic characterization, genetic analysis, and molecular mapping of a new mutant gene for male sterility in rice

Abstract

xs1 is a male-sterile rice mutant derived from a spontaneous mutation. The floret of the mutant, consisting of 6 stamens and 1 pistil, looks the same as that of the wild type except that the filaments are long and thin and the anthers are withered in white transparence. It is confirmed that xs1 is a no-pollen type of male-sterile mutant, for no pollen grains can be stained with I(2)-KI solution and the anther locules are always hollow. Anther transverse sections indicate that the mutant microspores are abnormally condensed and agglomerated to form a deeply stained cluster at the late microspore stage, which results in cessation of the vacuolation process of microspores, and, therefore, the mutant forms no functional pollens for reproduction. Genetic analysis of 4 F(2) populations and 3 BC(1)F(1) populations revealed that the mutation is controlled by a single recessive gene, termed VR1 (Vacuolation retardation 1). Screening of 432 F(2) mutant individuals derived from the cross of xs1 x G603 with simple sequence repeat markers revealed that VR1 is located between the molecular markers RM17411 and RM5030, at distances of 0.7 and 1.5 cM, respectively, on chromosome 4. VR1 is a new male fertility controlling gene located on chromosome 4 in rice.

Secretory lipid transfer protein OsLTPL94 acts as a target of EAT1 and is required for rice pollen wall development

“…We have previously identified an allelic mutant of eat1 , namely eat1‐5 , in the background of Minghui63 ( indica rice) by employing a map‐based cloning approach (Chu et al., 2010; Zuo et al., 2008; Figure S14). The eat1‐5 microspores were abnormally collapsed and degraded, and failed to form functional pollen grains, mimicking the defect phenotypes of eat1 reported by Ji et al.…”

Phenotypic Characterization, Genetic Analysis and Molecular Mapping of a New Floral Organ Mutant Gene in Rice

“…Floral structures of the mutant and wild-type plant were observed under an optical microscope before flowering. Pollen fertility was investigated after staining with 1% I2-KI solution [23]. Anthers of the florets were placed on slides with I2-KI solution and nipped into pieces with forceps to spill out pollen grains.…”

“…The total rice genomic DNA was isolated according to the method of Wang and Fang [28] and Zuo et al [23] with modifications. Powdered rice leaves were first incubated with the extraction buffer (100 mM Tris-Cl; 50 mM EDTA; 500 mM NaCl; 1.5% SDS; pH 8.0) at 65˚C, and then phenol-chloroform extraction and alcohol precipitation were performed.…”

“…In the 4 F 2 populations, all the segregation rates of wild type and the mutant plants fit the ratio of 3:1 (X 2 < X 2 0.05,1 = 3.84); and additionally, in the 2 BC 1 F 1 populations, the segregation rates fit the ratio of 1:1 (Table 1) (X 2 < X 2 0.05,1 = 3.84). The data was analyzed Chi-square test [23]. Therefore, the mutant trait was controlled by a single recessive gene, and termed srs2 (Spit rice spikelet 2).…”

Prioritising Genes with an Artificial Neural Network Comprising Medical Documents to Accelerate Positional Cloning in Biological Research

“…This is because the keyword 'salt tolerance' was mapped to the sodium ion transmembrane transporter gene AT4G10310, and Os01g0307500 was suggested as a homologue of AT4G10310. Using a no-pollen type of male-sterile mutant (xs1), Zuo et al (2008) revealed that mutant microspores are abnormally condensed and agglomerated to form a deeply stained cluster at the late microspore stage. This halts the microspore vacuolation process, and therefore, the mutant forms lack functional pollen.…”