Area of Specialization : Plant molecular physiology, Plant molecular biology, Cell biology
Research Interest : The primary research interest of my lab lies in the plant hormone auxin that influences almost all aspects of plant development from embryogenesis to senescence. Over the past decade aided by Arabidopsis genetics, a wealth of information underlying the molecular mechanism of action of this hormone has been understood. However, the pace has been slower for understanding the steps after transcription that engage the machinery of growth. In our lab we are investigating the role of this hormone from a broader perspective, trying to link upstream signaling events with downstream physiological responses.
We are currently trying to tease apart the regulators that are involved in controlling the auxin mediated root growth development, a process that is yet poorly understood. In an effort to do that, we are using a multidisciplinary approach combining physiology, cell biology, molecular biology, genomics, and biochemistry, and use Arabidopsis thaliana as study material. Recently we have shown that actin is one of the major regulators in auxin mediated root growth regulation. We also found that actin plays a minor role in targeting the auxin transport machineries and in controlling the cell elemental elongation as opposed to our current understanding. Surprisingly, actin also provided a basis for separating responses of the natural auxin IAA and its chemical analogue 2,4-D. The distinct differences of these two chemicals in regulating the downstream responses are consistent with our previous finding where we characterized an Arabidopsis mutant aar1, that shows only a 2,4-D specific resistance, yet responds to other auxins like wild-type. The molecular characterization of aar1 further revealed that a small acidic protein (SMAP1) confers the 2,4-D sensitivity of the plants and works up stream in auxin signaling pathway. These results are intriguing as it challenges our present concept that IAA and its chemical analogue 2,4-D evoke similar responses and share a common signal transduction pathway.
The research in my lab is currently focused on 1) elucidating the regulatory/ molecular mechanism of 2,4-D induced change in cytoskeletal structure and its impact on selective herbicidal action on monocots and dicots 2) investigating the role of actin in the sub cellular targeting of auxin efflux carriers and 3) auxin response in temperature stress and underlying mechanism. To know more about our research please visit our lab home page at http://news7a1.atm.iwate-u.ac.jp/~abidur/
Latest Publications :
Abidur Rahman, Alex Bannigan, Waheeda Sulaman, Priit Pechter, Elison B. Blancaflor, Tobias I. Baskin (2007) Auxin, actin and growth of the Arabidopsis thaliana primary root. The Plant Journal 50 (3), 514–528 [A must-read article selected by Faculty of 1000 Biology: comments by Professor Patrick Masson]
Abidur Rahman, Akari Nakasone, Tory Chhun, Chiharu Ooura, Kamal Kanti Biswas, Hirofumi Uchimiya, Seiji Tsurumi, Tobias I. Baskin, Atsushi Tanaka, Yutaka Oono (2006) A small acidic protein 1 (SMAP1) mediates responses of the Arabidopsis root to the synthetic auxin 2,4-dichlorophenoxyacetic acid. The Plant Journal 37(5)788-801 (Selected by the Chief Editor to be the featured article.)
Ranjan Swarup, Joanna Kargul, Alan Marchant, Daniel Zadik, Abidur Rahman, Rebecca Mills, Anthony Yemm, Sean May, Lorraine Williams, Paul Millner, Seiji Tsurumi, Ian Moore, Richard Napier, Ian D. Kerr and Malcolm J. Bennett (2004) Structure-Function Analysis of the presumptive Arabidopsis Auxin Permease AUX1. Plant Cell 16:3069-3083
Abidur Rahman, Satoko Hosokawa, Yutaka Oono, Taisaku Amakawa, Nobuharu Goto and Seiji Tsurumi (2002) Auxin-and ethylene-response during Arabidopsis root hair development dissected by auxin influx modulators. Plant Physiol. 130: 1908-1917
Abidur Rahman, Arifa Ahamed, Taisaku Amakawa T, Nobuharu Goto, Seiji Tsurumi (2001) Chromosaponin I specifically interacts with AUX1 protein in regulating the gravitropic response of Arabidopsis roots. Plant Physiol. 125:990-1000
