Potential involvement of drought-induced Ran GTPase CLRan1 in root growth enhancement in a xerophyte wild watermelon.
Enhanced root growth is known as the survival strategy of plants under drought. Previous proteome analysis in drought-resistant wild watermelon has shown that Ran GTPase, an essential regulator of cell division and proliferation, was induced in the roots under drought. In this study, two cDNAs were isolated from wild watermelon, CLRan1 and CLRan2, which showed a high degree of structural similarity with those of other plant Ran GTPases. Quantitative RT-PCR and promoter-GUS assays suggested that CLRan1 was expressed mainly in the root apex and lateral root primordia, whereas CLRan2 was more broadly expressed in other part of the roots. Immunoblotting analysis confirmed that the abundance of CLRan proteins was elevated in the root apex region under drought stress. Transgenic Arabidopsis overexpressing CLRan1 showed enhanced primary root growth, and the growth was maintained under osmotic stress, indicating that CLRan1 functions as a positive factor for maintaining root growth under stress conditions.
a Faculty of Agriculture, School of Agricultural, Biological and Environmental Sciences , Tottori University , Tottori , Japan.
Kinya
K
Akashi
b Graduate School of Biological Sciences , Nara Institute of Science and Technology (NAIST) , Ikoma , Japan.
Kazuya
K
Yoshimura
b Graduate School of Biological Sciences , Nara Institute of Science and Technology (NAIST) , Ikoma , Japan.
Masataka
M
Kajikawa
b Graduate School of Biological Sciences , Nara Institute of Science and Technology (NAIST) , Ikoma , Japan.
Kouhei
K
Hanada
b Graduate School of Biological Sciences , Nara Institute of Science and Technology (NAIST) , Ikoma , Japan.
Rina
R
Kosaka
a Faculty of Agriculture, School of Agricultural, Biological and Environmental Sciences , Tottori University , Tottori , Japan.
Atsushi
A
Kato
b Graduate School of Biological Sciences , Nara Institute of Science and Technology (NAIST) , Ikoma , Japan.
Akira
A
Katoh
a Faculty of Agriculture, School of Agricultural, Biological and Environmental Sciences , Tottori University , Tottori , Japan.
Yoshihiko
Y
Nanasato
c Arid Land Research Center , Tottori University , Tottori , Japan.
Hisashi
H
Tsujimoto
b Graduate School of Biological Sciences , Nara Institute of Science and Technology (NAIST) , Ikoma , Japan.
Akiho
A
Yokota
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D029773:Citrullus / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D009997:Osmotic Pressure; D018517:Plant Roots / Q000254:growth & development*; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014867:Water / Q000378:metabolism; D020931:ran GTP-Binding Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D012333:RNA, Messenger; D014867:Water; D020931:ran GTP-Binding Protein
Ran GTPase; arid region; drought avoidance; root growth; wild watermelon