Cadmium(Cd)is a non-essential toxic metal that is harmful to plants.To investigate the genetic mechanism of Cd tolerance in rice,quantitative trait loci(QTLs)associated with Cd tolerance at the seedling stage were ana...Cadmium(Cd)is a non-essential toxic metal that is harmful to plants.To investigate the genetic mechanism of Cd tolerance in rice,quantitative trait loci(QTLs)associated with Cd tolerance at the seedling stage were analyzed using a recombinant inbred line(RIL)population derived from a cross between PA64s and 93-11.A total of 36 QTLs associated with shoot length,root length,shoot dry weight,root dry weight and total dry weight were detected in Hangzhou and Lingshui of China.Among them,15 QTLs were identified under the control condition and 15 QTLs were identified under the Cd stress condition,and 6 QTLs for Cd tolerant coefficient were detected on chromosomes 1,3,7 and 9.The qCDSL1.1 and qCDSL1.2 were identified in Hangzhou and Lingshui,respectively,and had overlapping intervals on chromosome 1.To further confirm the effects of qCDSL1.1 and qCDSL1.2,we developed a chromosome segment substitution line(CSSL),CSSLqCDSL1,in 93-11 background harboring qCDSL1.1/qCDSL1.2 from PA64s.Compared to 93-11,CSSLqCDSL1 had increased shoot length under the Cd stress condition.These results pave the way for further isolation of those genes controlling Cd tolerance in rice and marker-assistant selection of rice elite varieties with Cd tolerance.展开更多
A gsnl4 mutant characterized by small grain size,narrow leaf and low seed-setting rate was obtained by ethyl methane sulfonate(EMS)mutagenesis of a japonica rice variety Wuyunjing 21.Genetic analysis showed that gsnl4...A gsnl4 mutant characterized by small grain size,narrow leaf and low seed-setting rate was obtained by ethyl methane sulfonate(EMS)mutagenesis of a japonica rice variety Wuyunjing 21.Genetic analysis showed that gsnl4 is a loss-of-function mutant.A single-base mutation in gsnl4 resulted in the substitution of Ser to Asn in the Piwi domain of OsAGOlb protein.CRISPR/Cas9-mediated editing of OsAGOlb yielded a mutant phenotypically resembling gsnl4.Furthermore,miRNA-Seq analysis showed that the transcript expression levels of miRNAs in the signal transduction pathways related to pollen development,leaf morphology and honnone activation were significantly different between the gsnl4 mutant and the wild type(WT)plants.Several miRNAs were downregulated,and their target genes were upregulated in gsnl4 mutants.The auxin content in the root tips of the gsnl4 mutant decreased,and the expression of most auxin-related genes was altered.In summary,GSNL4 not only regulates organ development by controlling cell division and expansion,but also plays an important role in regulating auxin transport in rice.展开更多
基金the National Natural Science Foundation of China(Grant No.31671761)the Agricultural Science and Technology Innovation Program,Shenzhen Science and Technology Program(Grant No.2017050414212249).
文摘Cadmium(Cd)is a non-essential toxic metal that is harmful to plants.To investigate the genetic mechanism of Cd tolerance in rice,quantitative trait loci(QTLs)associated with Cd tolerance at the seedling stage were analyzed using a recombinant inbred line(RIL)population derived from a cross between PA64s and 93-11.A total of 36 QTLs associated with shoot length,root length,shoot dry weight,root dry weight and total dry weight were detected in Hangzhou and Lingshui of China.Among them,15 QTLs were identified under the control condition and 15 QTLs were identified under the Cd stress condition,and 6 QTLs for Cd tolerant coefficient were detected on chromosomes 1,3,7 and 9.The qCDSL1.1 and qCDSL1.2 were identified in Hangzhou and Lingshui,respectively,and had overlapping intervals on chromosome 1.To further confirm the effects of qCDSL1.1 and qCDSL1.2,we developed a chromosome segment substitution line(CSSL),CSSLqCDSL1,in 93-11 background harboring qCDSL1.1/qCDSL1.2 from PA64s.Compared to 93-11,CSSLqCDSL1 had increased shoot length under the Cd stress condition.These results pave the way for further isolation of those genes controlling Cd tolerance in rice and marker-assistant selection of rice elite varieties with Cd tolerance.
基金supported by the National Natural Science Foundation of China(Grant Nos.31771887,31671761 and 32001491)supported by the National Natural Science Foundation of China(Grant Nos.31771887,31671761 and 32001491).
文摘A gsnl4 mutant characterized by small grain size,narrow leaf and low seed-setting rate was obtained by ethyl methane sulfonate(EMS)mutagenesis of a japonica rice variety Wuyunjing 21.Genetic analysis showed that gsnl4 is a loss-of-function mutant.A single-base mutation in gsnl4 resulted in the substitution of Ser to Asn in the Piwi domain of OsAGOlb protein.CRISPR/Cas9-mediated editing of OsAGOlb yielded a mutant phenotypically resembling gsnl4.Furthermore,miRNA-Seq analysis showed that the transcript expression levels of miRNAs in the signal transduction pathways related to pollen development,leaf morphology and honnone activation were significantly different between the gsnl4 mutant and the wild type(WT)plants.Several miRNAs were downregulated,and their target genes were upregulated in gsnl4 mutants.The auxin content in the root tips of the gsnl4 mutant decreased,and the expression of most auxin-related genes was altered.In summary,GSNL4 not only regulates organ development by controlling cell division and expansion,but also plays an important role in regulating auxin transport in rice.
