Arabidopsis cryptochrome-1 restrains lateral roots growth by inhibiting auxin transport.
Cryptochromes are blue-light photoreceptors that control many aspects of plant development. In this study, cryptochrome mutants of Arabidopsis were examined to assess the role of cryptchrome-1 (CRY1) in lateral roots growth. When grown in blue light for 12d, mutant seedlings (cry1) showed increased growth of lateral roots, while CRY1-overexpressing transgenic seedlings (CRY1ox) exhibited a marked decrease. Lateral roots growth of CRY1ox could be stimulated by auxin, but expression of PIN1 (efflux carrier of polar auxin transport) was strongly reduced. Contrary, the cry1 mutation showed the opposite effect, indicating that blue light and the auxin-signaling pathway interact in lateral roots growth of Arabidopsis. The free IAA content in CRY1ox roots was half of that in wild type and cry1 mutant roots. Moreover, the content of flavonoids (quercetin, kaempferol, isorhamnetin), which act as endogenous negative regulators of auxin transport, increased in CRY1ox seedlings. Taken together, these results suggest that Arabidopsis CRY1 restrains lateral roots growth by inhibiting auxin transport.
Bioenergy and Biomaterial Research Center, Bioscience and Biotechnology Institute, Hunan University, Changsha 410082, China.
Jianxin
J
Zeng
Qiming
Q
Wang
Jianzhong
J
Lin
Keqin
K
Deng
Xiaoying
X
Zhao
Dongying
D
Tang
Xuanming
X
Liu
D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects / Q000528:radiation effects; D002851:Chromatography, High Pressure Liquid; D056931:Cryptochromes / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007210:Indoleacetic Acids / Q000378:metabolism* / Q000494:pharmacology; D008027:Light; D009154:Mutation / Q000235:genetics; D010797:Phthalimides / Q000494:pharmacology; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism* / Q000528:radiation effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects
D029681:Arabidopsis Proteins; C538962:CRY1 protein, Arabidopsis; D056931:Cryptochromes; D007210:Indoleacetic Acids; D010797:Phthalimides; C002687:alpha-naphthylphthalamic acid