CYP704B1 is a long-chain fatty acid omega-hydroxylase essential for sporopollenin synthesis in pollen of Arabidopsis.
Sporopollenin is the major component of the outer pollen wall (exine). Fatty acid derivatives and phenolics are thought to be its monomeric building blocks, but the precise structure, biosynthetic route, and genetics of sporopollenin are poorly understood. Based on a phenotypic mutant screen in Arabidopsis (Arabidopsis thaliana), we identified a cytochrome P450, designated CYP704B1, as being essential for exine development. CYP704B1 is expressed in the developing anthers. Mutations in CYP704B1 result in impaired pollen walls that lack a normal exine layer and exhibit a characteristic striped surface, termed zebra phenotype. Heterologous expression of CYP704B1 in yeast cells demonstrated that it catalyzes omega-hydroxylation of long-chain fatty acids, implicating these molecules in sporopollenin synthesis. Recently, an anther-specific cytochrome P450, denoted CYP703A2, that catalyzes in-chain hydroxylation of lauric acid was also shown to be involved in sporopollenin synthesis. This shows that different classes of hydroxylated fatty acids serve as essential compounds for sporopollenin formation. The genetic relationships between CYP704B1, CYP703A2, and another exine gene, MALE STERILITY2, which encodes a fatty acyl reductase, were explored. Mutations in all three genes resulted in pollen with remarkably similar zebra phenotypes, distinct from those of other known exine mutants. The double and triple mutant combinations did not result in the appearance of novel phenotypes or enhancement of single mutant phenotypes. This implies that each of the three genes is required to provide an indispensable subset of fatty acid-derived components within the sporopollenin biosynthesis framework.
Dobritsa
Anna A
AA
Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA. dobritsa@uchicago.edu
Shrestha
Jay
J
Morant
Marc
M
Pinot
Franck
F
Matsuno
Michiyo
M
Swanson
Robert
R
Møller
Birger Lindberg
BL
Preuss
Daphne
D
D000483:Alleles; D017360:Arabidopsis / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D055162:Biocatalysis; D001704:Biopolymers / Q000096:biosynthesis*; D002338:Carotenoids / Q000096:biosynthesis*; D002874:Chromosome Mapping; D042926:Cytochrome P-450 CYP4A / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005816:Genetic Complementation Test; D006900:Hydroxylation; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity; D010636:Phenols / Q000378:metabolism; D010641:Phenotype; D011058:Pollen / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure
D029681:Arabidopsis Proteins; D001704:Biopolymers; D005227:Fatty Acids; D010636:Phenols; C009800:sporopollenin; D002338:Carotenoids; D042926:Cytochrome P-450 CYP4A
Nature. 1993 Jun 24;363(6431):715-7
8390620
Plant J. 1998 Dec;16(6):735-43
10069079
Science. 2003 Aug 1;301(5633):653-7
12893945
Plant Cell. 2009 Feb;21(2):507-25
19218397
J Exp Bot. 2008;59(9):2347-60
18544608
Protein Expr Purif. 2007 Nov;56(1):121-7
17826178
Plant J. 2009 Apr;58(2):246-59
19077165
Proc Natl Acad Sci U S A. 2007 Nov 13;104(46):18339-44
17991776
Genes Dev. 2001 Apr 15;15(8):939-44
11316788
Nature. 2001 Mar 15;410(6826):357-60
11268209
Z Naturforsch C J Biosci. 2002 Nov-Dec;57(11-12):1035-41
12562090
Plant J. 2004 Jul;39(2):170-81
15225283
J Biol Chem. 1964 Jul;239:2379-85
14209972
Plant Cell. 2002 Dec;14(12):2985-94
12468722
EMBO J. 2004 Jul 21;23(14):2903-13
15241470
FEBS J. 2007 Oct;274(19):5116-27
17868380
BMC Evol Biol. 2007 Aug 02;7:130
17683536
Plant Mol Biol. 2003 Sep;53(1-2):107-16
14756310
Plant Physiol. 1988 Jan;86(1):134-6
16665854
J Biol Chem. 2005 Oct 28;280(43):35881-9
16120613
Genome Res. 2004 Aug;14(8):1641-53
15289482
Plant J. 2008 Feb;53(3):437-49
18179651
Plant Physiol. 2009 Aug;150(4):1831-43
19525321
Plant Physiol. 2004 Jun;135(2):756-72
15208422
Methods Enzymol. 1996;272:51-64
8791762
J Biol Chem. 1997 Aug 1;272(31):19176-86
9235908
BMC Plant Biol. 2005 Oct 07;5:22
16212660
Curr Opin Biotechnol. 2003 Apr;14(2):151-62
12732316
J Biol Chem. 2001 Sep 28;276(39):36566-74
11429408
PLoS Genet. 2007 Oct;3(10):1848-61
17937500
Plant Physiol. 2004 Sep;136(1):2621-32
15375207
Proc Natl Acad Sci U S A. 2001 Aug 14;98(17):9694-9
11493698
J Chem Soc Perkin 1. 1966;1:16-22
5948281
Plant J. 2005 Jul;43(1):153-63
15960624
Yeast. 1999 Oct;15(14):1555-64
10514572
Biochem J. 1998 Jun 1;332 ( Pt 2):583-9
9601090
Plant Cell. 2007 May;19(5):1473-87
17496121
Science. 2006 Sep 15;313(5793):1596-604
16973872
Biochem J. 1999 Aug 15;342 ( Pt 1):27-32
10432296
Genes Dev. 2004 Apr 1;18(7):782-93
15082530
J Plant Physiol. 2009 May 15;166(8):787-96
19062129
Plant Physiol. 2005 Mar;137(3):1067-81
15709153
Nucleic Acids Res. 2007 Jan;35(Database issue):D863-9
17130150
Proc Natl Acad Sci U S A. 1991 Nov 1;88(21):9828-32
1682921
Plant J. 1997 Sep;12(3):615-23
9351246
Trends Plant Sci. 2008 May;13(5):236-46
18440267
Plant J. 2006 Feb;45(3):423-38
16412087
Biochem Biophys Res Commun. 1998 Feb 24;243(3):688-93
9500987