Arabidopsis ROP-interactive CRIB motif-containing protein 1 (RIC1) positively regulates auxin signalling and negatively regulates abscisic acid (ABA) signalling during root development.
Auxin and abscisic acid (ABA) modulate numerous aspects of plant development together, mostly in opposite directions, suggesting that extensive crosstalk occurs between the signalling pathways of the two hormones. However, little is known about the nature of this crosstalk. We demonstrate that ROP-interactive CRIB motif-containing protein 1 (RIC1) is involved in the interaction between auxin- and ABA-regulated root growth and lateral root formation. RIC1 expression is highly induced by both hormones, and expressed in the roots of young seedlings. Whereas auxin-responsive gene induction and the effect of auxin on root growth and lateral root formation were suppressed in the ric1 knockout, ABA-responsive gene induction and the effect of ABA on seed germination, root growth and lateral root formation were potentiated. Thus, RIC1 positively regulates auxin responses, but negatively regulates ABA responses. Together, our results suggest that RIC1 is a component of the intricate signalling network that underlies auxin and ABA crosstalk.
POSTECH-UZH Global Research Laboratory, Division of Molecular Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Korea.
Yunjung
Y
Choi
Yuree
Y
Lee
Soo Young
SY
Kim
Youngsook
Y
Lee
Jae-Ung
JU
Hwang
D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D055786:Gene Knockout Techniques; D005816:Genetic Complementation Test; D018525:Germination; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism* / Q000494:pharmacology; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D025941:Protein Interaction Mapping; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction
D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D008869:Microtubule-Associated Proteins; C547530:RIC1 protein, Arabidopsis; D049452:Green Fluorescent Proteins; D000040:Abscisic Acid