Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） an...Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.展开更多
Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that ca...Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon＇s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei＇s genetic distance and genetic identity between populations revealed a close association between geographically iso- lated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among- population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species.展开更多
It is well known that salinity has badly effect on plant growth all over the world and greatly reduces crop production in the affected regions.Selenium can function as an antioxidant in plants and also in low concentr...It is well known that salinity has badly effect on plant growth all over the world and greatly reduces crop production in the affected regions.Selenium can function as an antioxidant in plants and also in low concentration can promotes plant growth and produce tolerance against stress.This study was conducted in order to determine the effects of selenium(Se)application(0,4,8 and 16 mg L^-1)on phenylalanine ammonia-lyase(PAL)activity,phenol leakage and total phenolic content of garlic under salt stress(0,30,60 and 90 mM NaCl).The highest PAL activity was recorded at 60 and 90 mM NaCl salinity with application of 8mg Se L^-1.Also,when Se was added to the salt-stress garlic,the level of phenol leakage was decreased significantly at two levels of NaCl concentration(by 52%and 40%at 30 mM NaCl with application of 4 and 16 mg Se L^-1,and by 50%at 90 mM NaCl with application of 4mg Se L^-1,respectively)in comparison to the salt-stressed garlic without Se.The results showed that Se can increase the salt tolerance of garlic by protecting the cell membrane against lipid peroxidation.The highest concentration of phenols was recorded at 90 mM NaCl salinity level with application of 4 and 8 mg Se L^-1,that respectively produced 59%and 51%higher phenols than control treatment without Se.So,application of optimal Se level can increase the potential of garlic in a medium with relatively high level of NaCl.展开更多
A fragment of PAL (phenylalanine ammonia_lyase) gene was amplified by RT_PCR from poplar (Populus×euramericana cv. “74/76”) developing second xylem mRNA. It was cloned into pGEM-T Easy vector and identified by ...A fragment of PAL (phenylalanine ammonia_lyase) gene was amplified by RT_PCR from poplar (Populus×euramericana cv. “74/76”) developing second xylem mRNA. It was cloned into pGEM-T Easy vector and identified by restriction enzyme, PCR amplification and sequencing. The sequence of the amplified DNA fragment was 565 base pairs. Alignment with the P. kitakamiensis PAL cDNA sequence retrieved from EMBL nucleotide acid database (accession number D30656) showed that the first 400 base pairs in both sequences were almost identical. Therefore the fragment was part of PAL gene. And both of sense and anti-sense expressional vectors were constructed.展开更多
Phenylalanine ammonia lyase (PAL) has great values in industrial and potential medical applications, especially in the production of L phenylalanine from trans cinnamic acid. Strain breeding is important for the devel...Phenylalanine ammonia lyase (PAL) has great values in industrial and potential medical applications, especially in the production of L phenylalanine from trans cinnamic acid. Strain breeding is important for the development and applications of this bioprocess. In this article, mutiple ways for breeding of microbial strains containing PAL were reviewed in details, including direction screening, enrichment culture technique for isolating strains from nature sources, phsical and chemical mutagenesis for strain improvement, PAL molecular clone and genetic engineering, etc. The significance of protoplast techniques for breeding of Rhodotorula strains containing PAL was analysed and discussed.展开更多
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China (31101548)the Special Fund for Agro-Scientific Research in the Public Interest, China (201303014)+1 种基金funded by the China Agriculture Research System (CARS-25)the Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-IVFCAAS)
文摘Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.
基金supported by Shahid Chamran University of Ahvaz Fund(SHCUF)under Project No.SHCH_AGF_Grant 1394
文摘Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon＇s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei＇s genetic distance and genetic identity between populations revealed a close association between geographically iso- lated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among- population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species.
文摘It is well known that salinity has badly effect on plant growth all over the world and greatly reduces crop production in the affected regions.Selenium can function as an antioxidant in plants and also in low concentration can promotes plant growth and produce tolerance against stress.This study was conducted in order to determine the effects of selenium(Se)application(0,4,8 and 16 mg L^-1)on phenylalanine ammonia-lyase(PAL)activity,phenol leakage and total phenolic content of garlic under salt stress(0,30,60 and 90 mM NaCl).The highest PAL activity was recorded at 60 and 90 mM NaCl salinity with application of 8mg Se L^-1.Also,when Se was added to the salt-stress garlic,the level of phenol leakage was decreased significantly at two levels of NaCl concentration(by 52%and 40%at 30 mM NaCl with application of 4 and 16 mg Se L^-1,and by 50%at 90 mM NaCl with application of 4mg Se L^-1,respectively)in comparison to the salt-stressed garlic without Se.The results showed that Se can increase the salt tolerance of garlic by protecting the cell membrane against lipid peroxidation.The highest concentration of phenols was recorded at 90 mM NaCl salinity level with application of 4 and 8 mg Se L^-1,that respectively produced 59%and 51%higher phenols than control treatment without Se.So,application of optimal Se level can increase the potential of garlic in a medium with relatively high level of NaCl.
文摘A fragment of PAL (phenylalanine ammonia_lyase) gene was amplified by RT_PCR from poplar (Populus×euramericana cv. “74/76”) developing second xylem mRNA. It was cloned into pGEM-T Easy vector and identified by restriction enzyme, PCR amplification and sequencing. The sequence of the amplified DNA fragment was 565 base pairs. Alignment with the P. kitakamiensis PAL cDNA sequence retrieved from EMBL nucleotide acid database (accession number D30656) showed that the first 400 base pairs in both sequences were almost identical. Therefore the fragment was part of PAL gene. And both of sense and anti-sense expressional vectors were constructed.
文摘Phenylalanine ammonia lyase (PAL) has great values in industrial and potential medical applications, especially in the production of L phenylalanine from trans cinnamic acid. Strain breeding is important for the development and applications of this bioprocess. In this article, mutiple ways for breeding of microbial strains containing PAL were reviewed in details, including direction screening, enrichment culture technique for isolating strains from nature sources, phsical and chemical mutagenesis for strain improvement, PAL molecular clone and genetic engineering, etc. The significance of protoplast techniques for breeding of Rhodotorula strains containing PAL was analysed and discussed.
