title: Regulation of ATG6/Beclin-1  homologs by abiotic stresses and hormones in rice (Oryza sativa L.).
abstract: Autophagy,  a complex and conserved mechanism, serving as a defense response in all  eukaryotic organisms, is regulated by several proteins, among which ATG  proteins are the most important due to their involvement in autophagosome  formation. ATG6/Beclin-1 proteins, reported to be essential for autophagosome  formation and assigned as a conserved domain, were subjected to database  searches. We found three homologs in the rice (Oryza sativa) genome. A  phylogeny tree was constructed to establish their across species relationship,  which divided them into three distinct groups; two for plants, i.e., monocots  and dicots, and one for animals. Evolutionary study of this family by critical  amino acid conservation analysis revealed significant functional divergence.  The finding of important stress-related cis-acting elements in the  promoter region of rice ATG6 genes demonstrated their involvement in abiotic  stress responses. Furthermore, expression profiling of rice ATG6 genes  based on microarray data, as well as by semi-quantitative RT-PCR showed  differential expression when subjected to different stresses suggesting the  involvement of OsATG6 genes in abiotic stresses (heat, cold and drought)  and hormone (abscisic acid) responses. Analysis of co-expressed genes showed  that most of them annotated to DNA repair pathways and proteolysis, etc.  Collectively, these results suggest the involvement of OsATG6 genes in  different stresses, and provide a basis for further functional studies to  investigate the biological mechanism of action of these genes under abiotic  stresses.
authors.affiliation: State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.
authors.forename: R M
authors.initials: RM
authors.lastname: Rana
authors.forename: S
authors.initials: S
authors.lastname: Dong
authors.forename: Z
authors.initials: Z
authors.lastname: Ali
authors.forename: J
authors.initials: J
authors.lastname: Huang
authors.forename: H S
authors.initials: HS
authors.lastname: Zhang
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000737:chemistry*; D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000737:chemistry*; D000071186:Beclin-1; D019143:Evolution, Molecular; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000187:drug effects; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological / Q000187:drug effects* / Q000235:genetics; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D029681:Arabidopsis Proteins; D000071186:Beclin-1; D010937:Plant Growth Regulators; D010940:Plant Proteins; C519561:beclin 1 protein, Arabidopsis