The Wx gene expression plays a major role in determining the amylose content in the rice endosperm, although Wx alleles and their trans-acting genes like du genes are also known to genetically control the amylose content. Experiments were conducted to determine whether genes inhibiting the Wx expression respond similary to two Wx alleles, Wxa and Wxb, which are predominantly distributed in cultivated. A recessive mutant with chalky endosperm and showing an independent inheritance of wx was used in this study. Complementation tests showed that the mutant gene was allelic to du2 but the gene was designated as du2-2 as its phenotype was distinct. Nearisogenic lines (NILs) with different combinations of alleles at the Wx and du2-2 loci were then established and evaluated for the Wx gene expression. Waxy or chalky endosperms due to du2-2 were detected only in response to Wxb but not to Wxa, which may account for the fact that no du variants were detected in the Indica type. The potential use of du2-2 for improving the grain quality of the Indica type was discussed.
Both du-1 and du-2 have differential effects on Wx splicing in endosperm and pollen.Continuous planting of crops containing single disease resistance (R) genes imposes a strong selection for virulence in pathogen populations, often rendering the R gene ineffective. Increasing environmental temperatures may complicate R-gene-mediated disease control because high temperatures often promote disease development and reduceR gene effectiveness. Here, performance of one rice bacterial blight disease R gene was assessed in field and growth chamber studies to determine the influence of temperature on R gene effectiveness and durability. Disease severity and virulence of Xanthomonas oryzae pv. oryzae (Xoo) populations were monitored in field plots planted to rice with and without the bacterial blight R geneXa7 over 11 yr. The performance of Xa7 was determined in high- and low-temperature regimes in growth chambers. Rice with Xa7 exhibited less disease than lines without Xa7 over 11 yr, even though virulence of Xoo field populations increased. Xa7 restricted disease more effectively at high than at low temperatures. Other R genes were less effective at high temperatures.
In the rice genome, endo-1,4-b-D-glucanases form a multiple gene family including OsGLU3 which share high sequence similarity with KOR1 (2). OsGLU3is ubiquitously expressed in various tissues with strong expression in root tip, lateral root, and crown root primodia. OsGLU3contains four exons and three introns (Fig 2B). The putative OsGLU3 was predicted to contain a transmembrane domain, a cytosolic domain, and a catalytic domain (Supplemental Fig 3A). The mutation is located in the catalytic domain, which is highly conserved among the plant KOR1 homologs (Supplemental Fig 3B). qRT–PCR showed that the OsGLU3 is highly expressed in root tissue and has relatively lower expression in the other tissues. The OsGLU3–GUS expression was observed ubiquitously in the rice plants included in leaf veins, excoemums,and roots. the OsGLU3–GFP protein may reflect the native OsGLU3.OsGLU3 localizes in the plasma member and endosomes, and the export of OsGLU3 to the PM depends on vesicle transport. Phosphate starvation could induce root elongation inOsglu3-1.The phosphate starvation-induced primary root elongation and cellulose-content increase are abolished in Osglu3-2, which suggests that phosphate starvation-induced primary root elongation depends on the activity of OsGLU3.Suggesting that a single recessive gene was responsible for the mutant phenotype. Using 1 000 F2 mutant seedlings selected from the population, the mutation was mapped to a 56-kb region between S4-24837K and S4-24893K on chromosome 4. This region contains 14 open reading frames (ORFs), including a b-1,4-endoglucanase (OsGLU3, LOC_Os04g41970)(3).
In rice genome, the putative membrane-anchored endo-b-1,4-D-glucanases were encoded by three genes: OsGLU1, OsGLU2, and OsGLU3.Recently,Libertiniet al.(2004) reported that 15 endoglucanase genes were present in rice genome.that these proteins could be classified into four main clusters. One cluster contained OsGLU4, OsGLU8, OsGLU12, OsGLU13,OsGLU14 and OsGLU15. Another cluster contained OsGLU1, OsGLU2, OsGLU3, KOR and CEL3. The third cluster contained OsGLU5,OsGLU6, OsGLU7, OsGLU9, OsGLU10 and OsGLU11.OsGLU1to OsGLU10 each gene had different numbers of introns and exons. All proteins of the OsGLU family contained the EGase domain. The OsGLU1, OsGLU2 and OsGLU3 contained a predicted highly hydrophobic transmembrane motif in the N-terminal and belonged to the type II integral membrane protein anchored in the membrane. The results demonstrated thatOsGLU1, OsGLU2,OsGLU3 and OsGLU10 showed constitutive expression patterns in all the organs tested, and the OsGLU4, OsGLU5, OsGLU6, OsGLU9were abundant in roots and developing flowers of plants. The other two genes OsGLU7 and OsGLU8 showed relatively higher expression in rachis and developing flowers. These different expression patterns indicated multiple functions of these genes in different processes of plant growth and development. Specific and combinational expression of these genes may be essential for the formation or function of a given organ（2）.
The Osglu3-1 mutant has less cellulose in its roots and is defective in root cell elongation and division. However,theshoot development ofOsglu3-1seems ormal. In rice genome, the putative membrane-anchored endo-b-1,4-D-glucanases were encoded by three genes: OsGLU1, OsGLU2, and OsGLU3. Although all of them are expressed ubiquitously in the rice plant,OsGLU1 showed high expression in shoot tissue whilstOsGLU3is highly expressed inroot tissue.This indicates that the different expression pattern of the gene members might explain the root elongation defect of Osglu3-1. Consistently with this,the mutation of OsGLU1 also resulted in a reduction in shoot cell growth(2). In our study, the exogenous glucose inhibits the primary root elongation in the WT, which might due to the osmotic stress or the glucose serving as a signal. However, it could completely restore the mutant phenotype ofOsglu3-1and partially restore the phenotype of Osglu3-2. There were two possible explanations for this phenomenon. One is that OsGLU3 might function in trimming sterol residues from nascent glucan primers. When glucose, the substrate of cellulose synthesis, is added, it leads to an increase in the glucan chain.The addition of the glucan chains together with the residual OsGLU3 enzymatic activity of the point mutation mutant could restore the phenotypic defects ofOsglu3-1. However, this explanation could not explain the partial complementation of the loss-of-function mutantOsglu3-2by the exogenous glucose. The other possibility is that OsGLU3 might hydrolyze the matrix polysaccharides or the links between matrix polysaccharides and, together with cell wall-loosening enzymes (such as expansins), create space for new synthesis cellulose.Exogenous glucose leads to an induction of cellulose synthesis,which needs more space(3).
Labs working on this gene
- 1.National Key Lab of Plant Genomics,People’s Republic of China.
- 2.Institute of Genetics and Developmental Biology, Chinese Academy of Sciences ,People’s Republic of China.
- 3.The State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University,People’s Republic of China.
- 4.College of Science and Technology, Ningbo University, Ningbo, Zhejiang , China.
- 5.State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, People’s Republic of China.
- 6.Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou , People’s Republic of China.
- 7.Laboratoire de Biologie Cellulaire, Institut National de RechercheAgronomique
- 8.Universite´ de Rouen, CNRS UPRESA 6307, Faculte´ des Sciences
- 9.Centre de Physiologie Ve´ge´tale de l’Universite ´ Paul Sabatier, U.A.
- 1. Zhang J, Xu L, Wang F, Deng M, Yi K. Modulating the root elongation by phosphate/nitrogen starvation in an OsGLU3 dependant way in rice. Plant signaling & behavior. 2012;7(9):1144-5.
- 2. Zhou HL, He SJ, Cao YR, Chen T, Du BX, Chu CC, et al. OsGLU1, a putative membrane-bound endo-1,4-beta-D-glucanase from rice, affects plant internode elongation. Plant molecular biology. 2006;60(1):137-51.
- 3. Zhang JW, Xu L, Wu YR, Chen XA, Liu Y, Zhu SH, et al. OsGLU3, a putative membrane-bound endo-1,4-beta-glucanase, is required for root cell elongation and division in rice (Oryza sativa L.). Mol Plant. 2012;5(1):176-86.
- 4. Fre´de´ ric Nicol1, Isabelle His, Alain Jauneau, Samantha Vernhettes, Herve´ Canut, Herman Ho¨ fte. A plasma membrane-bound putative endo-1,4-betaD-glucanase is required for normal wall assembly and cell elongation inArabidopsis. The EMBO Journal. 1998;17(19):5563-76.
Similar to CEL5=CELLULASE 5 (Fragment)
NM_001067383.1 GI:115474502 GeneID:4344508
Oryza sativa Japonica Group Os08g0114200, complete gene.
Oryza sativa Japonica Group
ORGANISM Oryza sativa Japonica Group Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; Spermatophyta; Magnoliophyta; Liliopsida; Poales; Poaceae; BEP clade; Ehrhartoideae; Oryzeae; Oryza.
|Sequence Coding Region||
<gbrowseImage1> name=NC_008401:762215..764081 source=RiceChromosome08 preset=GeneLocation </gbrowseImage1>
<gbrowseImage2> name=NC_008401:762215..764081 source=RiceChromosome08 preset=GeneLocation </gbrowseImage2>
<aaseq>MCSWSLSSHTLTSPVRQAAMEPKSSSCGGAGIRLRLLVVLHLLL LVPSSAMAFNYADALAKSIIFFEGQRSGKLPPGNRMPWRADSGLTDGAQYNVDLVGGY YDAGDNVKFGLPMAFSTTMLAWSVLDFGKFMGAELPNARAAVRWGADYLLKAATATPG ALYVQVADPNQDHRCWERPEDMDTPRSVYRVTADKPGSDVAGETAAALAASSMVFRRA DPAYSARLLHAATQVFDFADRHRGSYSDSLASSVCPFYCSYSGYHDELLWGASWLHRA SRNASFMSYVEANGMQLGAGDDDYSFSWDDKRVGTKVLLAKGFLRNRLHGLELYKAHS DSYICSLVPGTASFQSRYTPGGLLYREGSSNMQYVTTATFLMLAYAKYLRSSGATASC GDGGGGARGEVSAAELVAVAKRQVDYILGKNPAGMSYMVGFGCRYPRRAHHRGASMPS VRAHPGRISCDAGFGYLHSGEPNPNVLVGAVVGGPDSRDAFADDRGNFAQSEPATYIN APLVGALAYFAGTTK</aaseq>
<dnaseqindica>74..358#444..1730#ACTCCCTCCTNTGCTGACAACAGATAACCACCTTTAACTGTAACTTTCCACAGCCTACCCCAGCCCTATA AAGCTGCCNCTCTCCTATCTCCCTTCGCTGACTCTCTTTTCAGACTCAGCCCACTTGCACCCAAGTGAAT TAACAGCCTTGTTGCTCACACAAAGCCTGTTTAGGTGGTCTTCTATATGGACATGCNTGACACTTGGTGC CAAAATCTGGGCCAGGGGGACTCCTTCGTGAGACCGGCCCCCTGTCCTGGCCCTCATTCCGTGAAGAGAT CCACCTGCGACCTCGGGTCCTCAGACCAGCCCAAGGAACATCTCACCAATTTCAAATCGGATCTCCTCGG CTTAGTGGCTGAAGACTGATGCTGCCCGATCGCCTCAGAAGCCCCNTGGACCATCACAGATGCCGAGCTT CGGGTAACTCTTACGGTGGAGGATTCCCAGCCATATGAAGACACCCTAGCTGGACGATCAGTCCTTGTCA AAAGTCTGACCCCTCAAACTCTACAGCCTCAATGGACCAGACCCTACCCGGTCATTTATAGCACACCAAC TGCCGTCCATCTGCAGGAACCTCTCCATTGGGTTCACCATTCCAGAATAAAGCCATGCCCATCAGACAGC CAGCTTGATCTCTCCTCTTCCTCCTGGAAGCCACAAGATTAGGCCGAGAGCCGATCAGACAAACAACCTA CAACCCTTAAGCTCCTGGCAGCGCCAAGCCAAGGCCATGCTTCCATGCAACACTCCTTCCAAATGGCCAT CCCAGCATGCTTCCAAGCAGGCTTCATCCGTTCCTCTGGACCCTCATCTCTTAAGACCTGCCGCCTATAA AAAGGATTATATCTTGAGACCCTATCCTCTAAAATTTTTTCCACACCCAAAACAAAAAATCTCTGGGTCA AAAGTCTAAAACGCTTAGGCTGGCAACCATCAGATCCTTGCCCATGGTGTCCTCAAGCCTACTCTCATGA AATGGACAACAGTACACGCATATGGGGCCAGTTCCACATATTTGGCAACCAGACCAGCATCCAGGACAAC ACAAAGTATGTTGTTTGTTGTTAGAGGGCTTGGGACATTTCACTCTTTGCCAGCCTCAGCTTAATCCAGG AGACAAAGATTATTTTCCTTATTATCTCTTCTGCATAGGATCTGCAATCAGAACTATTGAACTTCTCCAT TCAGACCGCCACTCACACCTATGGGAAAAGGGTAATGTATCATCGGCTTAGCAACAGGGTATACTATTCG TATGATGGAAAATGGGGACAAAAGGCTTTGGTACATCATAC</dnaseqindica>