title: Differential accumulation of glycinebetaine and choline monooxygenase in bladder hairs and lamina leaves of Atriplex gmelini under high salinity.
abstract: Atriplex gmelini is a halophyte and possesses bladder hairs on the leaf surface. It is also known to accumulate the osmoprotectant glycinebetaine (GB). However, it remains unclear whether GB and its biosynthetic enzyme choline monooxygenase (CMO) accumulate in the bladder hairs. Microscopic observation of young leaves showed many bladder hairs on their surfaces, but their total number decreased along with leaf maturity. Sodium Green fluorescent approach revealed Na(+) accumulation in bladder cells of young leaves when A. gmelini was grown at high salinity (250 mM NaCl). Due to fewer bladder hairs in mature leaves, Na(+) accumulation was mostly found in mesophyll cells of mature leaves under high salinity. GB accumulation was found at significant level in both bladder- and laminae-cells without any addition of NaCl and its content increased at high salinity. CMO was not found in bladder hairs or young leaf laminae. Instead, the CMO protein expression was observed in mature leaves and that showed increased accumulation with increasing concentration of NaCl. Furthermore, in situ hybridization experiments revealed the expression of a transporter gene for GB, AgBetT, in the bladder hairs. Based on these results, the synthesis and translocation of GB in A. gmelini were discussed.
authors.affiliation: Graduate School of Environmental and Human Sciences, Meijo University, Nagoya 468-8502, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsutsumi
authors.affiliation: Graduate School of Environmental and Human Sciences, Meijo University, Nagoya 468-8502, Japan; Plant Physiology and Biochemistry Laboratory, BIOTEC, Pathumthani 12120, Thailand.
authors.forename: Nana
authors.initials: N
authors.lastname: Yamada
authors.affiliation: Plant Physiology and Biochemistry Laboratory, BIOTEC, Pathumthani 12120, Thailand.
authors.forename: Suriyan
authors.initials: S
authors.lastname: Cha-um
authors.affiliation: Graduate School of Environmental and Human Sciences, Meijo University, Nagoya 468-8502, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Graduate School of Environmental and Human Sciences, Meijo University, Nagoya 468-8502, Japan; Research Institute, Meijo University, Nagoya 468-8502, Japan. Electronic address: takabe@meijo-u.ac.jp.
authors.forename: Teruhiro
authors.initials: T
authors.lastname: Takabe
mesh_terms: D027466:Atriplex / Q000235:genetics / Q000378:metabolism*; D001622:Betaine / Q000378:metabolism*; D002412:Cations; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D010105:Oxygenases / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology / Q000201:enzymology* / Q000235:genetics; D011188:Potassium / Q000378:metabolism; D054712:Salinity; D012964:Sodium / Q000378:metabolism
chemical_list: D002412:Cations; D001622:Betaine; D012964:Sodium; C105448:choline monooxygenase; D010105:Oxygenases; D011188:Potassium
keywords: Atriplex; Betaine; Bladder hairs; Choline monooxygenase; Salt stress