title: Isolation of the P5CS gene from reed canary grass and its expression under salt stress.
abstract: 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.
authors.affiliation: Institute of Grassland Science, China Agricultural University, Beijing, China.
authors.forename: L L
authors.initials: LL
authors.lastname: Cong
authors.affiliation: Department of Grassland Science, Sichuan Agricultural University, Ya'an, China.
authors.forename: X Q
authors.initials: XQ
authors.lastname: Zhang
authors.affiliation: Institute of Grassland Science, China Agricultural University, Beijing, China.
authors.forename: F Y
authors.initials: FY
authors.lastname: Yang
authors.affiliation: Institute of Grassland Science, China Agricultural University, Beijing, China.
authors.forename: S J
authors.initials: SJ
authors.lastname: Liu
authors.affiliation: Institute of Grassland Science, China Agricultural University, Beijing, China zywei@cau.edu.cn.
authors.forename: Y W
authors.initials: YW
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D050698:Glutamate-5-Semialdehyde Dehydrogenase / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D031783:Phalaris / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055049:Salt Tolerance / Q000235:genetics; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000235:genetics; D013997:Time Factors
chemical_list: D018076:DNA, Complementary; D009097:Multienzyme Complexes; D010940:Plant Proteins; D012965:Sodium Chloride; D011392:Proline; D050698:Glutamate-5-Semialdehyde Dehydrogenase; D017853:Phosphotransferases (Alcohol Group Acceptor)