TY - JOUR
T1 - Modulation of an RNA-binding protein by abscisic-acid-activated protein kinase
AU - Li, Jiaxu
AU - Kinoshita, Toshinori
AU - Pandey, Sona
AU - Ng, Carl K.Y.
AU - Gygi, Steven P.
AU - Shimazaki, Ken Ichiro
AU - Assmann, Sarah M.
N1 - Funding Information:
We thank H. Ho for HT–GST–WAVE1 baculovirus; B. Mayer for Nck constructs and proteins; R. Iggo for antibody to PIR121; J. Peterson and N. Ayad for discussions, technical help and critically reading the manuscript; and L. Ma for initial observations. This work was supported by the NIH (M.W.K.) the European Molecular Biology Organization (S.E.), the Human Frontier Science Program Organization (S.E.), the Danish National Research Foundation (M.M. and A.V.P.) and the Medical Sciences Training Program (MSTP) at Harvard Medical School (R.R.).
Funding Information:
We thank S. Gilroy and E. Kunze for the use of their confocal and fluorescence microscopes; M. Guiltinan for use of the gene gun; H. Ma for providing the SNF1 and SNF4 constructs; P. James for providing the PJ69-4A strain; L. Ding for assistance with AKIP1 constructs; and P. Minnich for technical support. This research was supported by NSF (S.M.A.) and partly supported by a Grant-in-Aid for Scientific Research on Priority Areas from Ministry of Education, Sports and Culture of Japan (K.S. and T.K.).
PY - 2002/8/15
Y1 - 2002/8/15
N2 - Protein kinases are involved in stress signalling in both plant and animal systems. The hormone abscisic acid mediates the responses of plants to stresses such as drought, salinity and cold. Abscisic-acid-activated protein kinase (AAPK)-found in guard cells, which control stomatal pores-has been shown to regulate plasma membrane ion channels. Here we show that AAPK-interacting protein 1 (AKIP1), with sequence homology to heterogeneous nuclear RNA-binding protein A/B, is a substrate of AAPK. AAPK-dependent phosphorylation is required for the interaction of AKIP1 with messenger RNA that encodes dehydrin, a protein implicated in cell protection under stress conditions. AAPK and AKIP1 are present in the guard-cell nucleus, and in vivo treatment of such cells with abscisic acid enhances the partitioning of AKIP1 into subnuclear foci which are reminiscent of nuclear speckles. These results show that phosphorylation-regulated RNA target discrimination by heterogeneous nuclear RNA-binding proteins may be a general phenomenon in eukaryotes, and implicate a plant hormone in the regulation of protein dynamics during rapid subnuclear reorganization.
AB - Protein kinases are involved in stress signalling in both plant and animal systems. The hormone abscisic acid mediates the responses of plants to stresses such as drought, salinity and cold. Abscisic-acid-activated protein kinase (AAPK)-found in guard cells, which control stomatal pores-has been shown to regulate plasma membrane ion channels. Here we show that AAPK-interacting protein 1 (AKIP1), with sequence homology to heterogeneous nuclear RNA-binding protein A/B, is a substrate of AAPK. AAPK-dependent phosphorylation is required for the interaction of AKIP1 with messenger RNA that encodes dehydrin, a protein implicated in cell protection under stress conditions. AAPK and AKIP1 are present in the guard-cell nucleus, and in vivo treatment of such cells with abscisic acid enhances the partitioning of AKIP1 into subnuclear foci which are reminiscent of nuclear speckles. These results show that phosphorylation-regulated RNA target discrimination by heterogeneous nuclear RNA-binding proteins may be a general phenomenon in eukaryotes, and implicate a plant hormone in the regulation of protein dynamics during rapid subnuclear reorganization.
UR - http://www.scopus.com/inward/record.url?scp=0037102432&partnerID=8YFLogxK
U2 - 10.1038/nature00936
DO - 10.1038/nature00936
M3 - Article
C2 - 12181571
AN - SCOPUS:0037102432
SN - 0028-0836
VL - 418
SP - 793
EP - 797
JO - Nature
JF - Nature
IS - 6899
ER -