ABP1 expression regulated by IAA and ABA is associated with the cambium periodicity in Eucommia ulmoides Oliv.
A cDNA clone of Eucommia ulmoides Oliv. encoding auxin binding protein 1 (ABP1), one of the putative receptors of auxin, was isolated, and the seasonal expression of ABP1 in relation to IAA and ABA annual variation was investigated by different technical approaches including RT-PCR, real-time PCR, northern blotting, western blotting, and immunolocalization. In the cambial region, ABP1 expression at both the protein and the mRNA level was found to be high, low, and remarkably scarce in the active, quiescent, and resting stages, respectively, during cambium periodicity. The signal abundance of ABP1 follows the opposite pattern to ABA accumulation and correlates with auxin responsiveness of the cambial tissues, suggesting a role for ABP1 in mediating auxin-dependent regulation of cambial activation in the activity-dormancy cycle. This paper attempts to explain why IAA would 'boost' the reactivation of a quiescent cambium, and not that of a resting cambium. Results also show that ABP1 expression is improved by IAA, while inhibited by ABA.
Hou
Hong-Wei
HW
College of Life Sciences, Peking University, Beijing 100871, China.
Zhou
Yu-Ting
YT
Mwange
Kalima-N'koma
KN
Li
Wan-Feng
WF
He
Xin-Qiang
XQ
Cui
Ke-Ming
KM
D000040:Abscisic Acid / Q000378:metabolism / Q000494:pharmacology*; D000595:Amino Acid Sequence; D031283:Eucommiaceae / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010507:Periodicity; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment
D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C046131:auxin receptor, plant; C030737:indoleacetic acid; D000040:Abscisic Acid