RESUMO
Reed canary grass (RCG) is a perennial grass traditionally cultivated for forage. It is also used as fuel to produce energy in Finland and Sweden, and other countries have expressed interest in the cultivation of RCG. In China, arable land is limited. Salinity is considered to be a major factor limiting plant crop development and productivity. To boost biofuel production of RCG and extend its range in saline soil, we seek to improve its salt tolerance. Proline acts as an osmolyte that accumulates when plants are subjected to abiotic stress. P5CS plays a crucial role in proline biosynthesis. We isolated a P5CS gene from RCG, designated B231P5CS (GenBank accession No. JQ622685). B231P5CS is a fragment (971 bp) that encodes a 323-amino acid polypeptide. We also cloned an actin gene fragment from RCG as a reference gene in expression analysis of B231P5CS gene. Expression analysis revealed that B231P5CS transcripts were upregulated in leaves after treatment with salt (200 mM NaCl) and that transcript levels of B231P5CS reached a maximum 12 h after exposure, which was 14.69 times the level in control plants. The trends of expression were exactly opposite in roots; transcripts were downregulated after salt treatment. Proline concentration increased in leaves after stress. In contrast, proline content of roots decreased up to 3.6-fold relative to controls. Changes in proline concentration after stress were correlated with B231P5CS expression. Our results suggest that B231P5CS is a stress-inducible gene and plays a non-redundant role in plant development. This gene may be used to improve stress tolerance of RGC and other bioenergy feedstock.
Assuntos
Glutamato-5-Semialdeído Desidrogenase/genética , Complexos Multienzimáticos/genética , Phalaris/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glutamato-5-Semialdeído Desidrogenase/classificação , Glutamato-5-Semialdeído Desidrogenase/metabolismo , Dados de Sequência Molecular , Complexos Multienzimáticos/classificação , Complexos Multienzimáticos/metabolismo , Phalaris/enzimologia , Phalaris/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/classificação , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Prolina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tolerância ao Sal/genética , Análise de Sequência de DNA , Cloreto de Sódio/farmacologia , Estresse Fisiológico/genética , Fatores de TempoRESUMO
Buffalo grass [Buchloe dactyloides (Nutt.) Engelm.] plants can be either male, female, or hermaphrodite (monoecious). As there is no morphological difference in the early vegetative growth of these three classes of plants, it is worthwhile to use molecular biological methods to attempt to identify the sex of a plant at this early growth period. In this study, we identified 23 plants that had a stable sex for over at least 3 years. Of these, 9 were male plants, 10 were female plants, and 4 were hermaphrodites. Screening of 300 RAPD primers identified a primer, namely S211 (5'-ttccccgcga-3'), which is capable of identifying male plants. The specific fragment was cloned, sequenced, and submitted to the GenBank database (accession No. JN982469). When used to identify the sex of 188 plants during their first growing season, the S211 primer correctly identified 85.8% of all male plants. Our results showed that the S211 primer can identify the male, and in doing so, it facilitates buffalo grass breeding work.