title: Differentially expressed galactinol synthase(s) in chickpea are implicated in seed vigor and longevity by limiting the age induced ROS accumulation.
abstract: Galactinol synthase (GolS) catalyzes the first and rate limiting step of Raffinose Family Oligosaccharide (RFO) biosynthetic pathway, which is a highly specialized metabolic event in plants. Increased accumulation of galactinol and RFOs in seeds have been reported in few plant species, however their precise role in seed vigor and longevity remain elusive. In present study, we have shown that galactinol synthase activity as well as galactinol and raffinose content progressively increase as seed development proceeds and become highly abundant in pod and mature dry seeds, which gradually decline as seed germination progresses in chickpea (Cicer arietinum). Furthermore, artificial aging also stimulates galactinol synthase activity and consequent galactinol and raffinose accumulation in seed. Molecular analysis revealed that GolS in chickpea are encoded by two divergent genes (CaGolS1 and CaGolS2) which potentially encode five CaGolS isoforms through alternative splicing. Biochemical analysis showed that only two isoforms (CaGolS1 and CaGolS2) are biochemically active with similar yet distinct biochemical properties. CaGolS1 and CaGolS2 are differentially regulated in different organs, during seed development and germination however exhibit similar subcellular localization. Furthermore, seed-specific overexpression of CaGolS1 and CaGolS2 in Arabidopsis results improved seed vigor and longevity through limiting the age induced excess ROS and consequent lipid peroxidation.
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Prafull
authors.initials: P
authors.lastname: Salvi
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Saurabh Chandra
authors.initials: SC
authors.lastname: Saxena
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Bhanu Prakash
authors.initials: BP
authors.lastname: Petla
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Nitin Uttam
authors.initials: NU
authors.lastname: Kamble
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Harmeet
authors.initials: H
authors.lastname: Kaur
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Pooja
authors.initials: P
authors.lastname: Verma
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Venkateswara
authors.initials: V
authors.lastname: Rao
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Shraboni
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Lab 203, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Manoj
authors.initials: M
authors.lastname: Majee
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000502:physiology; D029863:Cicer / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*; D004187:Disaccharides / Q000378:metabolism; D005700:Galactosyltransferases / Q000235:genetics / Q000378:metabolism*; D063245:Plant Development; D011887:Raffinose / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012639:Seeds / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*
chemical_list: D004187:Disaccharides; D017382:Reactive Oxygen Species; C013536:6 beta-galactinol; D005700:Galactosyltransferases; C096645:inositol 1-alpha-galactosyltransferase; D011887:Raffinose