title: Down-Regulation of a Nicotinate Phosphoribosyltransferase Gene, OsNaPRT1, Leads to Withered Leaf Tips.
abstract: Premature leaf senescence affects plant growth and yield in rice. NAD plays critical roles in cellular redox reactions and remains at a sufficient level in the cell to prevent cell death. Although numerous factors affecting leaf senescence have been identified, few involving NAD biosynthetic pathways have been described for plants. Here, we report the cloning and characterization of Leaf Tip Senescence 1 (LTS1) in rice (Oryza sativa), a recessive mutation in the gene encoding O. sativa nicotinate phosphoribosyltransferase (OsNaPRT1) in the NAD salvage pathway. A point mutation in OsNaPRT1 leads to dwarfism and the withered leaf tip phenotype, and the lts1 mutant displays early leaf senescence compared to the wild type. Leaf nicotinate and nicotinamide contents are elevated in lts1, while NAD levels are reduced. Leaf tissue of lts1 exhibited significant DNA fragmentation and H2O2 accumulation, along with up-regulation of genes associated with senescence. The lts1 mutant also showed reduced expression of SIR2-like genes (OsSRT1 and OsSRT2) and increased acetylation of histone H3K9. Down-regulation of OsSRTs induced histone H3K9 acetylation of senescence-related genes. These results suggest that deficiency in the NAD salvage pathway can trigger premature leaf senescence due to transcriptional activation of senescence-related genes.
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Liwen
authors.identifier: 0000-0003-4533-7232
authors.initials: L
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Deyong
authors.initials: D
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Shikai
authors.identifier: 0000-0003-4550-1645
authors.initials: S
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Gengmi
authors.initials: G
authors.lastname: Li
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Guojun
authors.identifier: 0000-0002-7556-4404
authors.initials: G
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Liang
authors.initials: L
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Xingming
authors.initials: X
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Weijun
authors.initials: W
authors.lastname: Ye
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Yongtao
authors.identifier: 0000-0001-5300-090X
authors.initials: Y
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Li
authors.initials: L
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Jiang
authors.initials: J
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Guangheng
authors.initials: G
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.).
authors.forename: Dali
authors.identifier: 0000-0003-2349-8633
authors.initials: D
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.) qianqian188@hotmail.com guolongbiao@caas.cn.
authors.forename: Qian
authors.identifier: 0000-0002-0349-4937
authors.initials: Q
authors.lastname: Qian
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China (L.W., D.R., S.H., G.L., G.D., L.J., X.H., W.Y., Y.C., L.Z., J.H., G.Z., Z.G., D.Z., Q.Q., L.G.); andAgricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China (S.H., Q.Q.) qianqian188@hotmail.com guolongbiao@caas.cn.
authors.forename: Longbiao
authors.initials: L
authors.lastname: Guo
mesh_terms: D000107:Acetylation / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D015536:Down-Regulation; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D006657:Histones / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation; D009525:Niacin / Q000494:pharmacology; D009536:Niacinamide / Q000494:pharmacology; D012275:Oryza / Q000033:anatomy & histology / Q000201:enzymology* / Q000235:genetics*; D010430:Pentosyltransferases / Q000378:metabolism*; D010641:Phenotype; D018515:Plant Leaves / Q000033:anatomy & histology* / Q000201:enzymology* / Q000254:growth & development; D036226:Seedlings / Q000235:genetics / Q000254:growth & development
chemical_list: D006657:Histones; D009536:Niacinamide; D009525:Niacin; D006861:Hydrogen Peroxide; D010430:Pentosyltransferases; C021864:nicotinate phosphoribosyltransferase