The regeneration rate of wheat immature embryo varies among genotypes, howbeit many elite agriculture wheat varieties have low regeneration rates. Optimization of tissue culture conditions and attempts of adding signa...The regeneration rate of wheat immature embryo varies among genotypes, howbeit many elite agriculture wheat varieties have low regeneration rates. Optimization of tissue culture conditions and attempts of adding signal molecules are effective ways to increase plant regeneration rate. Inter-culture is one of ways that have not been investigated in plant tissue culture. Moreover, the use of arabinogalactan proteins (AGPs) and hydrogen peroxide (H202) have been reported to increase regeneration rate in a few plant species other than wheat. The current research pioneeringly uses inter-culture of immature embryos of different wheat genotypes, and also investigates impacts of AGP and H2O2 on the induction of embryogenic calli and plant regeneration. As a result, high-frequency regeneration wheat cultivars Kenong 199 (KN 199) and Xinchun 9 (XC9), together with low-frequency regeneration wheat line Chinese Spring (CS), presented striking increase in the induction of embryogenic calli and plant regeneration rate of CS through inter-culture strategy, up to 52.19 and 67.98%, respectively. Adding 50 to 200 mg L-1 AGP or 0.005 to 0.01‰ H2O2 to the callus induction medium, enhanced growth of embryogenic calli and plant regeneration rate in quite a few wheat genotypes. At 50 mg L-1 AGP application level in callus induction medium plant regeneration rates of 8.49,409.06 and 283.16% were achieved for Jimai 22 (JM22), Jingdong 18 (JD18) and Yangmai 18 (YM18), respectively; whereas at 100 mg L-1 AGP level, CS (105.44%), Chuannong 16 (CN16) (80.60%) and Ningchun 4 (NC4) (62.87%) acted the best. Moreover CS (79.05%), JM22 (7.55%), CN16 (101.87%), YM18 (365.56%), Yangmai 20 (YM20) (10.48%), and CB301 (187.40%) were more responsive to 0.005 %o of H2O2, and NC4 (35.37%) obtained the highest shoot regeneration rates at 0.01%o of H2O2. Overall, these two methods, inter-culture and AGP (or H2O2) application, can be further applied to wheat transgenic research.展开更多
Arabinogalactan proteins(AGPs)are widely distributed in the plant kingdom and play a vital role during the process of plant sexual reproduction.In this study,we performed a comprehensive identification of the PbrAGPs ...Arabinogalactan proteins(AGPs)are widely distributed in the plant kingdom and play a vital role during the process of plant sexual reproduction.In this study,we performed a comprehensive identification of the PbrAGPs expressed in pear pollen and further explored their influences on pollen tube growth.Among the 187 PbrAGPs that were found to be expressed in pear pollen tubes,38 PbrAGPs were specifically expressed in pollen according to the RNA-seq data.The PbrAGPs were divided into two groups of highly expressed and specifically expressed in pear pollen.We further tested their expression patterns using RT-PCR and RT-qPCR.Most of the PbrAGPs were expressed in multiple tissues and their expression levels were consistent with reads per kilobase per million map reads(RPKM)values during pollen tube growth,implying that PbrAGPs might be involved in the regulation of pear pollen tube growth.We also constructed phylogenetic trees to identify the functional genes in pear pollen tube growth.Therefore,19 PbrAGPs(PbrAGP1 to PbrAGP19)were selected to test their influences on pollen tube growth.Recombinant proteins of the 19 PbrAGP-His were purified and used to treat pear pollen,and 11 of the PbrAGP-His recombinant proteins could promote pear pollen tube growth.Additionally,pollen tube growth was inhibited when the expression levels of PbrAGP1 and PbrAGP5 were knocked down using an antisense oligonucleotide assay.PbrAGP1 and PbrAGP5 were localized in the plasma membrane and might not alter the distribution of pectin in the pollen tube.In summary,this study identified the PbrAGPs expressed in pear pollen and lays the foundation for further exploring their functions in pollen tube growth.展开更多
Arabinogalactan proteins(AGPs)are widely distributed in plant cells.Fasciclin-like AGPs(FLAs)belong to a subclass of AGPs that play important roles in plant growth and development.However,little is known about the bio...Arabinogalactan proteins(AGPs)are widely distributed in plant cells.Fasciclin-like AGPs(FLAs)belong to a subclass of AGPs that play important roles in plant growth and development.However,little is known about the biological functions of rice FLA.Herein,we report the identification of a male-sterile mutant of DEFECTIVE EXINE AND APERTURE PATTERNING1(DEAP1)in rice.The deap1 mutant anthers produced aberrant pollen grains with defective exine formation and a flattened aperture annulus and exhibited slightly delayed tapetum degradation.DEAP1 encodes a plasma membrane-associated member of groupⅢplant FLAs and is specifically and temporally expressed in reproductive cells and the tapetum layer during male development.Gene expression studies revealed reduced transcript accumulation of genes related to exine formation,aperture patterning,and tapetum development in deap1 mutants.Moreover,DEAP1 may interact with two rice D6 PROTEIN KINASE-LIKE3 s(OsD6PKL3s),homologs of a known Arabidopsis aperture protein,to affect rice pollen aperture development.Our findings suggested that DEAP1 is involved in male reproductive development and may affect exine formation and aperture patterning,thereby providing new insights into the molecular functions of plant FLAs in male fertility.展开更多
Abstract: Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP e...Abstract: Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP epitopes); JIM 8 (recognizes a subset of AGP epitopes); and JIM 5 and JIM 7 (epitopes of pectins esterified to various degrees). In the stem apex meristem (SAM) of the cucumber, epitopes of MAC 207, JIM 7, and JIM 5 were localized in the cells from second to third peripheral layers when the sex organ primodium began to differentiate; epitopes of MAC 207 and JIM 5 were also detected in the ragged edge cells. A very dense labeling signal with MAC 207 was observed in the carpel and pistil primodium. The AGP epitopes recognized by JIM 8 were localized in the anther of the male flower and the anther-like portion of the stagnant stamen of the female flower. This suggests that the AGPs and pectins in the SAM of the cucumber are closely associated with the differentiation of the SAM, from meristematic cells to floral primodium. The subset of AGPs recognized by JIM 8 may play an important role in stamen formation.展开更多
To determine the most effective dose of arabinogalactan-protein (AGP) in regeneration medium, mature embryos of genotypes in three different ploidy levels (Triticum aestivum L. cv. Ikizce-96, Triticum durum Desf. c...To determine the most effective dose of arabinogalactan-protein (AGP) in regeneration medium, mature embryos of genotypes in three different ploidy levels (Triticum aestivum L. cv. Ikizce-96, Triticum durum Desf. cv. Mirzabey and Hordeum vulgare L. cv. Tokak) were used to establish an efficient plant regeneration system for cereals. Percentage of callus production, capacity of regeneration were calculated, and also culture effect, root, stem, and total plant length of regenerant plants were observed in six different regeneration media (MS control, MS+2, 5, 7, 10, 12 mg L-1 AGP) in these three different genotypes. According to the results, the highest amount of callus production was found in Ikizce-96 as 93.75% using 5 mg L-1 dicamba and 1 mg L-1 kinetin in induction medium. However, the most improved callus was observed in diploid barley Tokak as 179.95 mg in weight and 6.18 mm in diameter, respectively. The highest regeneration capacity was observed in the dose of 5 mg L-1 AGP in MS of all the genotypes and hexaploid wheat Ikizce-96 gave the best results with the highest regeneration capacity and culture effects (94.86 and 92.5%) in the same dose of AGE These results indicated that effective dose of AGP in regeneration medium increase plant regeneration in calli derived from cereal mature embryos.展开更多
A fiberless seed mutant (fl) was identified in a commercial cotton ( Gossypium hirsutum L.) variety Xu Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ...A fiberless seed mutant (fl) was identified in a commercial cotton ( Gossypium hirsutum L.) variety Xu Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ovule, as was characterized by analysis of genes related to fiber differentiation and development. Two genes, fl E6 and FL E6, were cloned from fl integument cells and FL fiber or integument cells, respectively. Compared with FL E6, fl E6 showed a dramatic change in nucleotide sequence: (1) FL E6 contained a tandem repetitive sequence in which GGCTCA (Gly Ser) is repeated five times between the 82nd and the 93rd codon from the first ATG codon, while in fl E6 the same sequence is repeated four times; (2) The fl E6 gene encodes a polypeptide of 241 amino acids but lacks two codons between the 90th and 93rd codon and three between the 171st and 174th relative to FL E6; (3) There are also 12 nucleotide substitutions which would result in 7 amino acid differences between fl E6 and FL E6. Analysis of RT PCR and Northern Blot showed that expression of the fl E6 gene is suppressed in the fl integument cells, but highly expressed in FL fiber cells. The difference between fl E6 and FL E6 may be associated with lower expression of fl E6 in the fl integument cells. Searches of protein databases with the FL E6 gene sequence showed similarity to the protein backbones of two arabinogalactan proteins (AGPs), one from the filtrate of suspension cultured cells of Pyrus communis (AGPPc2) and the other from Nicotiana alata (AGPNa2). Although the function of the FL E6 protein in differentiation and development of cotton fiber cells is not known, the data indicate that the mutation of fl E6 gene from FL E6 gene may inhibit the fiber cell initiation from epidermal cells of the outer integument of the ovule.展开更多
基金financially supported in part by the National Key Project for Tansgenic Study, Ministry of Agriculture of China(2011ZX08010-004)
文摘The regeneration rate of wheat immature embryo varies among genotypes, howbeit many elite agriculture wheat varieties have low regeneration rates. Optimization of tissue culture conditions and attempts of adding signal molecules are effective ways to increase plant regeneration rate. Inter-culture is one of ways that have not been investigated in plant tissue culture. Moreover, the use of arabinogalactan proteins (AGPs) and hydrogen peroxide (H202) have been reported to increase regeneration rate in a few plant species other than wheat. The current research pioneeringly uses inter-culture of immature embryos of different wheat genotypes, and also investigates impacts of AGP and H2O2 on the induction of embryogenic calli and plant regeneration. As a result, high-frequency regeneration wheat cultivars Kenong 199 (KN 199) and Xinchun 9 (XC9), together with low-frequency regeneration wheat line Chinese Spring (CS), presented striking increase in the induction of embryogenic calli and plant regeneration rate of CS through inter-culture strategy, up to 52.19 and 67.98%, respectively. Adding 50 to 200 mg L-1 AGP or 0.005 to 0.01‰ H2O2 to the callus induction medium, enhanced growth of embryogenic calli and plant regeneration rate in quite a few wheat genotypes. At 50 mg L-1 AGP application level in callus induction medium plant regeneration rates of 8.49,409.06 and 283.16% were achieved for Jimai 22 (JM22), Jingdong 18 (JD18) and Yangmai 18 (YM18), respectively; whereas at 100 mg L-1 AGP level, CS (105.44%), Chuannong 16 (CN16) (80.60%) and Ningchun 4 (NC4) (62.87%) acted the best. Moreover CS (79.05%), JM22 (7.55%), CN16 (101.87%), YM18 (365.56%), Yangmai 20 (YM20) (10.48%), and CB301 (187.40%) were more responsive to 0.005 %o of H2O2, and NC4 (35.37%) obtained the highest shoot regeneration rates at 0.01%o of H2O2. Overall, these two methods, inter-culture and AGP (or H2O2) application, can be further applied to wheat transgenic research.
基金supported by the earmarked fund for China Agriculture Research System(CARS-28-37)the Agricultural Science and Technology Innovation Project of Shandong Academy of Agricultural Sciences,China(CXGC2022E21)+1 种基金the Youth Foundation of Shandong Institute of Pomology,China(GSS2022QN11)the Natural Science Foundation of Shandong Province,China(ZR2019BC075,ZR2020MC141,and ZR2021MC177)。
文摘Arabinogalactan proteins(AGPs)are widely distributed in the plant kingdom and play a vital role during the process of plant sexual reproduction.In this study,we performed a comprehensive identification of the PbrAGPs expressed in pear pollen and further explored their influences on pollen tube growth.Among the 187 PbrAGPs that were found to be expressed in pear pollen tubes,38 PbrAGPs were specifically expressed in pollen according to the RNA-seq data.The PbrAGPs were divided into two groups of highly expressed and specifically expressed in pear pollen.We further tested their expression patterns using RT-PCR and RT-qPCR.Most of the PbrAGPs were expressed in multiple tissues and their expression levels were consistent with reads per kilobase per million map reads(RPKM)values during pollen tube growth,implying that PbrAGPs might be involved in the regulation of pear pollen tube growth.We also constructed phylogenetic trees to identify the functional genes in pear pollen tube growth.Therefore,19 PbrAGPs(PbrAGP1 to PbrAGP19)were selected to test their influences on pollen tube growth.Recombinant proteins of the 19 PbrAGP-His were purified and used to treat pear pollen,and 11 of the PbrAGP-His recombinant proteins could promote pear pollen tube growth.Additionally,pollen tube growth was inhibited when the expression levels of PbrAGP1 and PbrAGP5 were knocked down using an antisense oligonucleotide assay.PbrAGP1 and PbrAGP5 were localized in the plasma membrane and might not alter the distribution of pectin in the pollen tube.In summary,this study identified the PbrAGPs expressed in pear pollen and lays the foundation for further exploring their functions in pollen tube growth.
基金supported by funds from the National Natural Science Foundation of China(31901482,31971863,31971867 and 32171966)the Open Research Fund of the State Key Laboratory of Hybrid Rice(Hunan Hybrid Rice Research Centre,2016KF10)the Sichuan Province Science and Technology Support Program(2021YFYZ0016,2021YFYZ0027,2020YJ0139)。
文摘Arabinogalactan proteins(AGPs)are widely distributed in plant cells.Fasciclin-like AGPs(FLAs)belong to a subclass of AGPs that play important roles in plant growth and development.However,little is known about the biological functions of rice FLA.Herein,we report the identification of a male-sterile mutant of DEFECTIVE EXINE AND APERTURE PATTERNING1(DEAP1)in rice.The deap1 mutant anthers produced aberrant pollen grains with defective exine formation and a flattened aperture annulus and exhibited slightly delayed tapetum degradation.DEAP1 encodes a plasma membrane-associated member of groupⅢplant FLAs and is specifically and temporally expressed in reproductive cells and the tapetum layer during male development.Gene expression studies revealed reduced transcript accumulation of genes related to exine formation,aperture patterning,and tapetum development in deap1 mutants.Moreover,DEAP1 may interact with two rice D6 PROTEIN KINASE-LIKE3 s(OsD6PKL3s),homologs of a known Arabidopsis aperture protein,to affect rice pollen aperture development.Our findings suggested that DEAP1 is involved in male reproductive development and may affect exine formation and aperture patterning,thereby providing new insights into the molecular functions of plant FLAs in male fertility.
文摘Abstract: Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP epitopes); JIM 8 (recognizes a subset of AGP epitopes); and JIM 5 and JIM 7 (epitopes of pectins esterified to various degrees). In the stem apex meristem (SAM) of the cucumber, epitopes of MAC 207, JIM 7, and JIM 5 were localized in the cells from second to third peripheral layers when the sex organ primodium began to differentiate; epitopes of MAC 207 and JIM 5 were also detected in the ragged edge cells. A very dense labeling signal with MAC 207 was observed in the carpel and pistil primodium. The AGP epitopes recognized by JIM 8 were localized in the anther of the male flower and the anther-like portion of the stagnant stamen of the female flower. This suggests that the AGPs and pectins in the SAM of the cucumber are closely associated with the differentiation of the SAM, from meristematic cells to floral primodium. The subset of AGPs recognized by JIM 8 may play an important role in stamen formation.
文摘To determine the most effective dose of arabinogalactan-protein (AGP) in regeneration medium, mature embryos of genotypes in three different ploidy levels (Triticum aestivum L. cv. Ikizce-96, Triticum durum Desf. cv. Mirzabey and Hordeum vulgare L. cv. Tokak) were used to establish an efficient plant regeneration system for cereals. Percentage of callus production, capacity of regeneration were calculated, and also culture effect, root, stem, and total plant length of regenerant plants were observed in six different regeneration media (MS control, MS+2, 5, 7, 10, 12 mg L-1 AGP) in these three different genotypes. According to the results, the highest amount of callus production was found in Ikizce-96 as 93.75% using 5 mg L-1 dicamba and 1 mg L-1 kinetin in induction medium. However, the most improved callus was observed in diploid barley Tokak as 179.95 mg in weight and 6.18 mm in diameter, respectively. The highest regeneration capacity was observed in the dose of 5 mg L-1 AGP in MS of all the genotypes and hexaploid wheat Ikizce-96 gave the best results with the highest regeneration capacity and culture effects (94.86 and 92.5%) in the same dose of AGE These results indicated that effective dose of AGP in regeneration medium increase plant regeneration in calli derived from cereal mature embryos.
文摘A fiberless seed mutant (fl) was identified in a commercial cotton ( Gossypium hirsutum L.) variety Xu Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ovule, as was characterized by analysis of genes related to fiber differentiation and development. Two genes, fl E6 and FL E6, were cloned from fl integument cells and FL fiber or integument cells, respectively. Compared with FL E6, fl E6 showed a dramatic change in nucleotide sequence: (1) FL E6 contained a tandem repetitive sequence in which GGCTCA (Gly Ser) is repeated five times between the 82nd and the 93rd codon from the first ATG codon, while in fl E6 the same sequence is repeated four times; (2) The fl E6 gene encodes a polypeptide of 241 amino acids but lacks two codons between the 90th and 93rd codon and three between the 171st and 174th relative to FL E6; (3) There are also 12 nucleotide substitutions which would result in 7 amino acid differences between fl E6 and FL E6. Analysis of RT PCR and Northern Blot showed that expression of the fl E6 gene is suppressed in the fl integument cells, but highly expressed in FL fiber cells. The difference between fl E6 and FL E6 may be associated with lower expression of fl E6 in the fl integument cells. Searches of protein databases with the FL E6 gene sequence showed similarity to the protein backbones of two arabinogalactan proteins (AGPs), one from the filtrate of suspension cultured cells of Pyrus communis (AGPPc2) and the other from Nicotiana alata (AGPNa2). Although the function of the FL E6 protein in differentiation and development of cotton fiber cells is not known, the data indicate that the mutation of fl E6 gene from FL E6 gene may inhibit the fiber cell initiation from epidermal cells of the outer integument of the ovule.