Inhibition of phospholipase C disrupts cytoskeletal organization and gravitropic growth in Arabidopsis roots.
The phospholipase protein superfamily plays an important role in hormonal signalling and cellular responses to environmental stimuli. There is also growing evidence for interactions between phospholipases and the cytoskeleton. In this report we used a pharmacological approach to investigate whether inhibiting a member of the phospholipase superfamily, phospholipase C (PLC), affects microtubules and actin microfilaments as well as root growth and morphology of Arabidopsis thaliana seedlings. Inhibiting PLC activity using the aminosteroid U73122 significantly inhibited root elongation and disrupted root morphology in a concentration-dependent manner, with the response being saturated at 5 μM, whereas the inactive analogue U73343 was ineffective. The primary root appeared to lose growth directionality accompanied by root waving and formation of curls. Immunolabelling of roots exposed to increasingly higher U73122 concentrations revealed that the normal transverse arrays of cortical microtubules in the elongation zone became progressively more disorganized or depolymerized, with the disorganization appearing within 1 h of incubation. Likewise, actin microfilament arrays also were disrupted. Inhibiting PLC using an alternative inhibitor, neomycin, caused similar disruptions to both cytoskeletal organization and root morphology. In seedlings gravistimulated by rotating the culture plates by 90°, both U73122 and neomycin disrupted the normal gravitropic growth of roots and etiolated hypocotyls. The effects of PLC inhibitors are therefore consistent with the notion that, as with phospholipases A and D, PLC likewise interacts with the cytoskeleton, alters growth morphology, and is involved in gravitropism.
Andreeva
Zornitza
Z
School of Biological Sciences, University of Sydney, Sydney, NSW, Australia.
Barton
Deborah
D
Armour
William J
WJ
Li
Min Y
MY
Liao
Li-Fen
LF
McKellar
Heather L
HL
Pethybridge
Kylie A
KA
Marc
Jan
J
D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology*; D003599:Cytoskeleton / Q000187:drug effects / Q000201:enzymology*; D004963:Estrenes / Q000494:pharmacology; D018522:Gravitropism / Q000187:drug effects*; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology*; D011760:Pyrrolidinones / Q000494:pharmacology; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors / Q000378:metabolism*
D004963:Estrenes; D011760:Pyrrolidinones; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D010738:Type C Phospholipases
J Biol Chem. 2001 Jul 27;276(30):28252-60
11373276
Biochim Biophys Acta. 1989 Feb 13;979(1):105-12
2537103
Biochim Biophys Acta. 2009 Sep;1791(9):927-35
19289179
Plant Cell. 2007 Apr;19(4):1235-50
17468261
Nature. 2002 Feb 14;415(6873):806-9
11845211
Plant Cell Physiol. 2001 Feb;42(2):214-22
11230576
Plant Physiol. 2009 Sep;151(1):155-67
19633235
New Phytol. 2007;176(1):37-43
17692076
Plant J. 2008 Jan;53(2):380-92
18047472
Plant Cell. 2007 Jan;19(1):281-95
17259265
Cell Signal. 2007 Aug;19(8):1701-12
17478077
Curr Opin Plant Biol. 2004 Dec;7(6):712-8
15491921
Curr Opin Plant Biol. 2009 Dec;12(6):728-34
19854097
Plant Cell. 2004 Jun;16(6):1506-20
15155883
Mol Plant. 2008 Nov;1(6):1056-66
19825603
Proc Natl Acad Sci U S A. 2008 Mar 18;105(11):4489-94
18337510
Plant Physiol. 1998 Dec;118(4):1139-45
9847088
Plant Physiol Biochem. 2006 Feb-Mar;44(2-3):143-51
16644231
Plant Cell. 2003 Sep;15(9):1990-2002
12953106
Curr Opin Plant Biol. 2002 Oct;5(5):408-14
12183179
Plant Biol (Stuttg). 2008 Nov;10(6):725-31
18950430
Plant Cell. 2002 Jan;14(1):33-46
11826297
Mol Pharmacol. 2008 Nov;74(5):1203-14
18682550
Proc Natl Acad Sci U S A. 1999 May 11;96(10):5838-43
10318971
Plant Cell. 2006 Jun;18(6):1438-53
16648366
J Biol Chem. 2005 Feb 4;280(5):3723-30
15548524
Plant J. 1995 Feb;7(2):211-20
7704045
Plant J. 2008 Oct;56(1):116-31
18557839
Plant Physiol. 2004 Jul;135(3):1822-37
15247406
J Gen Physiol. 2005 Sep;126(3):243-62
16129772
J Lipid Res. 2009 Apr;50 Suppl:S260-5
19098305
Plant Physiol Biochem. 2008 Jul;46(7):627-37
18534862
Planta. 2001 Feb;212(3):392-403
11289604
Plant Cell. 1998 Nov;10(11):1927-40
9811799
Plant Physiol. 2007 Jan;143(1):213-24
17085513
Planta. 2009 Oct;230(5):925-33
19672622
Proc Natl Acad Sci U S A. 1999 Feb 16;96(4):1779-84
9990101
Plant Physiol. 2006 Feb;140(2):746-60
16384898
Annu Rev Plant Physiol Plant Mol Biol. 2001 Jun;52:211-231
11337397
New Phytol. 2008;178(2):267-282
18221245
Biochim Biophys Acta. 2009 Sep;1791(9):869-75
19394438
Adv Space Res. 2003;31(10):2215-20
14686435
J Biol Chem. 2005 Feb 25;280(8):6897-905
15579910
Plant Physiol. 2002 Sep;130(1):22-46
12226484
Plant Cell Physiol. 2003 Jul;44(7):687-96
12881496
Biochemistry. 1998 Apr 21;37(16):5549-57
9548939
Phytochemistry. 2007 Jun;68(11):1564-71
17466344
Science. 2006 Jun 9;312(5779):1491-5
16627697
Plant Physiol. 2001 Mar;125(3):1499-507
11244128
Annu Rev Plant Biol. 2003;54:691-722
14503008
Cell Res. 2009 Oct;19(10):1191-204
19736566
Plant Mol Biol. 2009 Mar;69(4):437-49
18982413
Nature. 2002 May 9;417(6885):193-6
12000963
Development. 2000 Oct;127(20):4443-53
11003843
J Neurosci. 2002 Mar 1;22(5):1668-78
11880496
Plant J. 2007 Dec;52(6):1014-26
17908156
Plant Cell. 2001 Sep;13(9):2143-58
11549769
Plant Physiol Biochem. 2006 Oct;44(10):581-9
17079154
Plant Physiol. 2000 Dec;124(4):1493-506
11115865
Plant Signal Behav. 2007 Jul;2(4):240-4
19516994
J Biol Chem. 2002 Dec 27;277(52):50683-92
12388543
J Lipid Mediat Cell Signal. 1995 Jan;11(1):81-91
7728419
Plant Cell. 2008 Feb;20(2):396-410
18281505
Plant Cell Physiol. 2009 Apr;50(4):889-903
19264788