Project description:To investigate the genetic relationship between two major grain length loci GS3 and qGL3, we developed the near-isogenic lines (NILs), NIL-GS3 (GS3/qGL3), NIL-qgl3 (gs3/qgl3), NIL-GS3/qgl3 (GS3/qgl3) in the background of 93-11 (gs3/qGL3) by crossing and MAS approach.
Project description:To investigate the genetic relationship between two major grain length loci GS3 and qGL3, we developed the near-isogenic lines (NILs), NIL-GS3 (GS3/qGL3), NIL-qgl3 (gs3/qgl3), NIL-GS3/qgl3 (GS3/qgl3) in the background of 93-11 (gs3/qGL3) by crossing and MAS approach. Four samples was analyzed: three near-isogenic lines (NILs), NIL-GS3 (GS3/qGL3), NIL-qgl3 (gs3/qgl3), NIL-GS3/qgl3 (GS3/qgl3) and their background of 93-11. Every sample had three independed duplications. And the primary panicle with 3-6 cm length from the three NILs and 93-11 were used for RNA preparation and hybrid with Rice Genome OneArray Microarray (Phalanx Biotech Group).
Project description:Grain length is a prominent determinant for the grain weight and appearance quality of rice. To elucidate the genetic basis of the control of grain length, we conducted quantitative trait locus (QTL) mapping to determine a genomic interval responsible for the a long-grain phenotype observed in a japonica cultivar HD385 by using an F2:3 population and recombinant inbred line (RIL) population, which is are derived from a cross between the long-grain japonica cultivar HD385 and short-grain japonica cultivar Nipponbare (NIP). This led to the identification of a novel QTL, which is located on chromosome 3, for grain length, named qIGL1 (for Increased Grain Length 1); the HD385-derived allele showed enhancement effects on grain length, and such an allele as well as NIP-derived allele are were thus designated qigl1 HD385 and qIGL1NIP, respectively. Genetic analysis revealed that qigl1HD385 displayed semi-dominant effects on grain length. To further narrow down the qIGL1 region, we developed a few advanced backcross populations to determine the precise location of qIGL1. Eventually, qIGL1 was delimited to a 70.8-kb region containing 9 open reading frames (ORFs). A comprehensive analysis indicated that ORF6 and ORF9, separately corresponding to LOC_Os03g30530 and LOC_Os03g30550, are were found to carry base substitutions and/or deletions, which resulted in changes or losses of amino acid residues. However, these alterations in coding sequences does did not significantly change the expression levels of both ORFs. To further elucidate the mechanisms behind the increases of grain length conferred by qigl1HD385, we generated a pair of near-isogenic lines (NILs), termed NIL-qigl1HD385 and NIL-qIGL1NIP, and discovered that introduction of qigl1HD385 into the NIP background significantly lead resulted into the elevations of grain length and 1000-grain weight. Closer inspection of outer epidermal cells of grain surfaces of both lines revealed that the cell length and width in the longitudinal direction are were significantly longer in NIL-qigl1HD385 compared with in NIL-qIGL1NIP, which may might stem partly from the downregulation of several cell cycle-related genes. Hence, our study studies identify identified a new semi-dominant natural allele contributing to the increase of grain length, and further shed light on the regulatory mechanisms of grain length.
Project description:Fruit length is a key domestication trait that affects crop yield and appearance quality. Cucumber fruits vary from 5~60 cm in length. Despite multiple fruit length QTLs have been identified, the underlying genes and regulatory mechanisms are poorly understood. Map-based cloning identified a nonsynonymous SNP (G to A) in CRABS CLAW (CsCRC) confers the major effect fruit length QTL FS5.2. CsCRCA is a rare allele only exist in Xishuangbanna cucumber with round fruits. Construction of near-isogenic line (NIL) of CsCRCA led to 34~39% reduction in fruit length. Introduction of CsCRCG into the NIL rescued the short-fruit phenotype, and knockdown of CsCRCG resulted in reduced fruit length and decreased cell size. RNA-seq results showed that an auxin responsive protein CsARP1 expressed decreased in CsCRC-RNAi lines. Further, an auxin responsive protein Further, CsARP1 is the downstream target gene of CsCRCG, instead of CsCRCA. Knockout of CsARP1 produced decreased fruit length with smaller cells. Hence, our work suggested that CsCRCG positively regulates fruit elongation through transcriptional activation of CsARP1 and thus enhanced cell expansion. Utilization of CsCRC alleles provides a new strategy to manipulate fruit length in cucumber breeding.
Project description:To learn more about the role of FRUITFULL (FUL), in pistil/silique development, we performed a ChIP-seq experiment to identify direct targets of FUL in the pistil/silique.
Project description:Pistil development is an important developmental process that directly affects the yield of Prunus sibirica. Through transcriptome sequencing analysis of clones with abortive pistil (No. 595) and normal pistil (No. 28) of Prunus sibirica, a total of 1950 significantly differentially expressed genes were obtained, among which 1000 genes were up-regulated and 950 genes were down-regulated. The results provide a theoretical basis for further investigation of the formation mechanism of pistil abortion.
Project description:Pollen tubes extend through pistil tissues and are guided to ovules where they release sperm for fertilization. Although pollen tubes can germinate and elongate in a synthetic medium, their trajectory is random and their growth rates are slower compared to growth in pistil tissues. Furthermore, interaction with the pistil renders pollen tubes competent to respond to guidance cues secreted by specialized cells within the ovule. The molecular basis for this potentiation of the pollen tube by the pistil remains uncharacterized. We used a surgical procedure to obtain large quantities of uncontaminated pollen tubes that grew through the pistil and defined their transcriptome by microarray analysis. We also characterized the transcriptome of in vitro-grown pollen tubes (for 0.5hours or 4hours) and dessicated mature pollen in Arabidopsis.