Polygalacturonase-inhibiting proteins （PGIPs） are extracellular proteins that belong to the leucine-rich repeat （LRR） protein superfamily. PGIPs inhibit fungal polygalacturonases （PGs） and promote accumulation o...Polygalacturonase-inhibiting proteins （PGIPs） are extracellular proteins that belong to the leucine-rich repeat （LRR） protein superfamily. PGIPs inhibit fungal polygalacturonases （PGs） and promote accumulation of oligogalacturonides, which activate plant defense responses. PGIPs play important roles in resistance to infection of pathogens. In this study, reverse transcriptase-polymerase chain reaction （RT-PCR） and RNA ligase-mediated rapid amplification of cDNA ends （RLM-RACE） were used to isolate the full-length PGIP cDNA from Populus deltoides （GenBank accession no. of PdPGIP2 and PdPGIP4：EF684913 and EF684912）. Domain analysis revealed that the deduced amino acid sequences of PdPGIP2 and PdPGIP4 had a typical PGIP topology. Phylogenetic analysis of known PGIPs indicated that the two PdPGIPs were clustered to the defense-related PGIP clade. Using real-time RT-PCR, the expression patterns of the two PdPGIPs following treatment with a fungal pathogen and defense-related signaling molecules were studied. The expression levels of PdPGIP2 and PdPGIP4 were both up-regulated when inoculated with the phytopathogenic fungus Marssonina brunnea. Therefore, it was proposed that the two PGIPs might be involved in the resistance to Marssonina brunnea in P. deltoides.展开更多
Using the reference sequences of pgip genes in GenBank,a fragment of 930 bp covering the open reading frame(ORF) of rice Ospgip1(Oryza sativa polygalacturonase-inhibiting protein 1) was amplified.The prokaryotic expre...Using the reference sequences of pgip genes in GenBank,a fragment of 930 bp covering the open reading frame(ORF) of rice Ospgip1(Oryza sativa polygalacturonase-inhibiting protein 1) was amplified.The prokaryotic expression product of the gene inhibited the growth of Rhizoctonia solani,the causal agent of rice sheath blight,and reduced its polygalacturonase activity.Bioinformatic analysis showed that OsPGIP1 is a hydrophobic protein with a molecular weight of 32.8 kDa and an isoelectric point(pI) of 7.26.The protein is mainly located in the cell wall of rice,and its signal peptide cleavage site is located between the 17th and 18th amino acids.There are four cysteines in both the N-and C-termini of the deduced protein,which can form three disulfide bonds(between the 56th and 63rd,the 278th and 298th,and the 300th and 308th amino acids).The protein has a typical leucine-rich repeat(LRR) domain,and its secondary structure comprises α-helices,β-sheets and irregular coils.Compared with polygalacturonase-inhibiting proteins(PGIPs) from other plants,the 7th LRR is absent in OsPGIP1.The nine LRRs could form a cleft that might associate with proteins from pathogenic fungi,such as polygalacturonase.展开更多
Brassica campestris male fertility 19 （BcMF19; GenBank accession number GQ902048.1）, a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, whi...Brassica campestris male fertility 19 （BcMF19; GenBank accession number GQ902048.1）, a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, which is learned from the previous in situ hybridization study. In the present study, we constructed antisense-silenced plants of BcMF19 using B. campestris ssp. chinensis to validate this prediction. The morphology of the pistils, long anthers, and short anthers was significantly affected in 35sbcmf19 compared with the control samples. 4＇-6-Diamidino-2-phenylindole staining revealed that two generative nuclei and one large vegetative nucleus were not affected in the mutant compared with control. Statistical analysis of Alexander＇s staining results showed that 96% of the control pollen grains had vitality, whereas only 86% of the mutant pollen grains did. Under scanning electron microscopy, the mutant demonstrated numerous abnormal pollen grains and resembled dried persimmon. The frequency of normal pollen grains was approximately 18%. Under transmission electron microscopy, the pollen intine during the binucleate and mature pollen stages in 35sbcmf19 exhibited abnormal thickening, especially at the germinal furrows, compared with control. In vitro pollen germination test showed that the tips of the mutant pollen tubes transformed into globular alveoli and stopped growing compared with control. On the other hand, in vivo pollen germination test suggested that BcMF19 affected the pollen tube extension in the pistil. These findings indicate that BcMF19 is essential to the pollen development and pollen tube extension orB. campestris ssp. chinensis.展开更多
基金the National Basic Research Program of China (No 2007CB116307)Forestry Scientific and Technical Supporting Programs (No 2006BAD01A15-3)
文摘Polygalacturonase-inhibiting proteins （PGIPs） are extracellular proteins that belong to the leucine-rich repeat （LRR） protein superfamily. PGIPs inhibit fungal polygalacturonases （PGs） and promote accumulation of oligogalacturonides, which activate plant defense responses. PGIPs play important roles in resistance to infection of pathogens. In this study, reverse transcriptase-polymerase chain reaction （RT-PCR） and RNA ligase-mediated rapid amplification of cDNA ends （RLM-RACE） were used to isolate the full-length PGIP cDNA from Populus deltoides （GenBank accession no. of PdPGIP2 and PdPGIP4：EF684913 and EF684912）. Domain analysis revealed that the deduced amino acid sequences of PdPGIP2 and PdPGIP4 had a typical PGIP topology. Phylogenetic analysis of known PGIPs indicated that the two PdPGIPs were clustered to the defense-related PGIP clade. Using real-time RT-PCR, the expression patterns of the two PdPGIPs following treatment with a fungal pathogen and defense-related signaling molecules were studied. The expression levels of PdPGIP2 and PdPGIP4 were both up-regulated when inoculated with the phytopathogenic fungus Marssonina brunnea. Therefore, it was proposed that the two PGIPs might be involved in the resistance to Marssonina brunnea in P. deltoides.
基金supported by the Programs of Natural Science Foundation of Jiangsu Province,China(Grant Nos.BK2008223and BK2010305)Transgenic Major Special Funds in China(Grant No.2009ZX08001-014B)
文摘Using the reference sequences of pgip genes in GenBank,a fragment of 930 bp covering the open reading frame(ORF) of rice Ospgip1(Oryza sativa polygalacturonase-inhibiting protein 1) was amplified.The prokaryotic expression product of the gene inhibited the growth of Rhizoctonia solani,the causal agent of rice sheath blight,and reduced its polygalacturonase activity.Bioinformatic analysis showed that OsPGIP1 is a hydrophobic protein with a molecular weight of 32.8 kDa and an isoelectric point(pI) of 7.26.The protein is mainly located in the cell wall of rice,and its signal peptide cleavage site is located between the 17th and 18th amino acids.There are four cysteines in both the N-and C-termini of the deduced protein,which can form three disulfide bonds(between the 56th and 63rd,the 278th and 298th,and the 300th and 308th amino acids).The protein has a typical leucine-rich repeat(LRR) domain,and its secondary structure comprises α-helices,β-sheets and irregular coils.Compared with polygalacturonase-inhibiting proteins(PGIPs) from other plants,the 7th LRR is absent in OsPGIP1.The nine LRRs could form a cleft that might associate with proteins from pathogenic fungi,such as polygalacturonase.
基金supported by the National Basic Research Program of China (2012CB113900)the National Natural Science Foundation of China (31071805)the Key Sci-Technology Project of Zhejiang Province, China (2010C12004)
文摘Brassica campestris male fertility 19 （BcMF19; GenBank accession number GQ902048.1）, a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, which is learned from the previous in situ hybridization study. In the present study, we constructed antisense-silenced plants of BcMF19 using B. campestris ssp. chinensis to validate this prediction. The morphology of the pistils, long anthers, and short anthers was significantly affected in 35sbcmf19 compared with the control samples. 4＇-6-Diamidino-2-phenylindole staining revealed that two generative nuclei and one large vegetative nucleus were not affected in the mutant compared with control. Statistical analysis of Alexander＇s staining results showed that 96% of the control pollen grains had vitality, whereas only 86% of the mutant pollen grains did. Under scanning electron microscopy, the mutant demonstrated numerous abnormal pollen grains and resembled dried persimmon. The frequency of normal pollen grains was approximately 18%. Under transmission electron microscopy, the pollen intine during the binucleate and mature pollen stages in 35sbcmf19 exhibited abnormal thickening, especially at the germinal furrows, compared with control. In vitro pollen germination test showed that the tips of the mutant pollen tubes transformed into globular alveoli and stopped growing compared with control. On the other hand, in vivo pollen germination test suggested that BcMF19 affected the pollen tube extension in the pistil. These findings indicate that BcMF19 is essential to the pollen development and pollen tube extension orB. campestris ssp. chinensis.
