Os06g0194900

The rice Os06g0194900 is the second gene of Sus gene family.

Annotated Information

Function

In rice three genes encoding for sucrose synthase (Sus),six genes comprise the entire rice Sus gene family.The six SUS genes can be classified into three recognized Sus groups, the Sus1 group (SUS1, 2and3),the SusA group (SUS4) and the NG (SUS5 and 6), It has been reported that sugar metabolism of rice seedlings is affected by hypoxia typically caused by submergence, and that Sus activity is suggested to be one of the key factors for the altered sugar metabolism in rice plants under submerged condition. overall Sus activity and expression of SUS2 increased significantly in seedlings germinated and grown in hypoxia (submerged conditions), suggesting a role in increasing sucrose metabolism as a response to environmental stress.Sucrose is cleaved in vivo either by sucrose synthase (Sus) (UDP-glucose: D-fructose 2-glucosyl-transferase, EC 2.4.1.13) or by invertase. Sus catalyzes the reversible conversion of sucrose and UDP into UDP-glucose and fructose. There is considerable evidence to indicate that Sus plays a major role(s) in metabolism in a number of different growth processes within a variety of sink tissues.Sus is also proposed to supply UDP-glucose for cellulose synthesis in the cell wall, and in cotton fiber which is supported by experimental evidence from antisense suppression of the enzyme.Recently a growing body of evidence suggests that one of the major roles of Sus is to channel UDP-glucose to the synthesis of cell-wall polysaccharides such as cellulose

Expression

Figure1. The transcript levels of the SUS genes in various rice tissues(from reference )..jpg

Expression of different Sus genes is spatially and temporally regulated and is differentially modulated in response to anoxia, low temperatures and osmotic stress,the expression of Sus genes is also differentially affected by sugars. Sus transcripts were detected in a wide range of tissues and at different developmental stages, indicating that Sus is involved in numerous and diverse growth processes in the rice plant. SUS2 was shown to be expressed in a wide range of tissues, suggesting that it may perform a number of housekeeping role(s)

Sus gene expression has also been reported to be induced in response to environmental stresses such as hypoxia and cold. Sus is reported to be encoded by multiple genes which have distinct and partially overlapping expression patterns. For example, maize has at least three genes encoding Sus, Sh1, Sus1 and Sus3 .

The mRNA levels for the SUS genes were highest in elongating sink organs such as roots, developing leaf blades and elongating uppermost internodes, with SUS1 and 2 being the isoforms predominantly expressed within these tissues. In contrast to this, SUS transcript levels in the mature leaf blades and leaf sheaths were low. The transcript levels of each SUS gene were plotted individually to examine specific expression patterns (Figure 1).

• SUS2 transcript levels were higher in root and internode tissue than other tissues examined.In all of the internode segments the transcripts of SUS1 and SUS2 together accounted for most of the SUS transcripts.

• SUS2 was most highly expressed in the bottom segment and decreased in subsequent segments before a slight increase in the top two segments.Overall SUS2 expression levels were considerably lower than those for SUS1.

• SUS2 was abundantly expressed in the early stage of the grain filling at 1 and 2 DAF, then increased and reached maximal levels during 5–10 DAF, and decreased thereafter.

• SUS2 was highly expressed in the developing caryopsis, correlating strongly with the stage of rapid increase in grain dry weight,and for a longer period thanSUS3, which implies that SUS2,along with SUS3 and SUS4, plays an important role in the grain filling process.

• SUS2 was in the phloem in addition to the mesophyll, RSuS2 was evenly distributed in seed tissues other than the endosperm, RSus2 is ubiquitously expressed,may play a house keeping role in providing sucrose to the sink tissues in general.
• the expression of RSus2 requires newly synthesized proteins induced by sucrose and/or starvation. RSus2 may have an important biological function in rice cells other than as a housekeeping gene.
• The transcription rates of RSus2 were similar in cells grown in the sucrose-free and sucrose-containing media, suggesting that there was constitutive expression of RSus2 mRNA in cells under vary-ing sugar availability.

Evolution

the evolution of multiple SS genes is not for the need of diversified catalytic functions but to meet the differential temporal and spatial requirements of the catalytic function according to the scheme of plant development and in response to environmental changes.this trend may be especially enhanced in the rice where the plant must adapt to the aerobic( leaf,stem,and grain) and anaerobic (root) conditions simultaneously and accumulate starch in a short period of the life span. Sequence similarities in SUS proteins from rice and maize indicate that RSus2 is closely related to maize Sus as is RSUSl to Sh1.The amino acid sequences deduced from RSUS2 and RSUS3 share an 89.6%identity.The set wo genes maybe evolved from the same ancestor after the divergence of RSUSl.

Knowledge Extention

• sucrose synthase (SS) genes in Populus expression patterns were constitutive and partially overlapping but diverse.
• In maize, the genes encoding for SuS, Sus1 and Sh1,show contrasting carbohydrate responses; that is,Sus1 is upregulated while Sh1 is downregulated in the presence of abundant carbohydrate supplies.

Labs working on this gene

• National Agricultural Research Center, 1-2-1 Inada, Joetsu, Niigata 943-0193, Japan
• Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan 106, R.O.C
• Department of Agronomy, National Taiwan University, Taipei, Taiwan 106, R.O.C.

Structured Information

Gene Name	Os06g0194900
Description	Sucrose synthase 2 (EC 2.4.1.13)
Version	NM_001063582.1 GI:115466895 GeneID:4340386
Length	5882 bp
Definition	Oryza sativa Japonica Group Os06g0194900, complete gene.
Source	Oryza sativa Japonica Group ORGANISM Oryza sativa Japonica Group Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; Spermatophyta; Magnoliophyta; Liliopsida; Poales; Poaceae; BEP clade; Ehrhartoideae; Oryzeae; Oryza.
Chromosome	Chromosome 6
Location	Chromosome 6:4795629..4801510
Sequence Coding Region	4795896..4795943,4796041..4796179,4796291..4796535,4796666..4796984,4797324..4797548 ,4797637..4797803,4797886..4798002,4798087..4798260,4798357..4798452 ,4798535..4798751,4798847..4798965,4799115..4799307,4799391..4799542 ,4799632..4799752,4800164..4800258
Expression	GEO Profiles:Os06g0194900
Genome Context	<gbrowseImage1> name=NC_008399:4795629..4801510 source=RiceChromosome06 preset=GeneLocation </gbrowseImage1>
Gene Structure	<gbrowseImage2> name=NC_008399:4795629..4801510 source=RiceChromosome06 preset=GeneLocation </gbrowseImage2>
Coding Sequence	<cdnaseq>atggctgccaagctagctcgcctccacagtctccgcgaacgcctcggtgccaccttctcgtctcatcccaatgagttgattgcactcttctctaggtatgttaaccagggaaagggaatgctccagcgtcaccagctgcttgcggagttcgatgccttgatcgaagctgacaaagagaaatatgctccctttgaagacattctccgggctgctcaggaagccattgtgctgccgccctgggttgcactggccatcaggccaaggcctggtgtctgggactacattcgggtgaatgtaagtgagttggcagtggaagagctgagtgtttctgagtacttggcattcaaggaacagcttgttgatggacacaccaacagcaactttgttcttgagcttgattttgagcccttcaatgcctccttcccgcgcccgtccatgtccaagtccatcggaaatggggtgcagttccttaaccgtcacctgtcgtccaagttgttccaggacaaggagagcctctaccccttgctgaacttcctgaaagcccataaccacaagggcacgacaatgatgctgaatgacagaattcagagccttcgtgggctccaatcatcccttagaaaggcagaagaatatctgatgggcattcctcaagacacgccctactcggagttcaaccacaggttccaagagctcggtttggagaagggttggggtgactgtgcaaagcgtgtgcttgacaccatccacttgcttcttgaccttcttgaggcccctgatccggccaacttggagaagttccttggaactattccaatgatgttcaatgttgttatcctgtctccgcatggatactttgcccaatccaatgtgttgggataccctgatactggtggtcaggttgtgtacattttggaccaagtccgcgctttggagaatgagatgcttttgaggatcaagcagcaaggccttgatatcacacctaagatcctcattgtaaccaggctgttgcctgatgctgttggtactacatgcggccagcgtgtggagaaggttattggaactgagcacactgacattcttcgtgttccattcaggagtgagaatggtatcctccgcaagtggatctcccgttttgatgtctggccattcctggaaacatacactgaggatgttgcaaacgaaattatgagggaaatgcaagccaaacctgatctcatcattggcaattacagtgatggaaaccttgttgccactctgctggctcacaaattaggagttacccagtgtaccattgctcatgccttggagaaaaccaaataccccaactcagacatatacttggacaagtttgacagccagtaccacttctcatgccaattcactgctgatcttatcgccatgaatcacactgatttcatcatcaccagtacattccaagaaattgctggaagcaaggacactgtggggcagtatgaatcacacattgcattcacccttcctgggctttaccgagttgtgcatggcatagatgtttttgatcccaagttcaacattgtctctcctggagctgacatgagtgtctacttcccgtacaccgaggctgacaagaggctcactgctttccaccctgaaattgaggagcttctctacagtgaagtcgagaacgatgaacacaagtttgtattgaaggacaagaacaagccaatcatcttctccatggctcgtcttgaccgagtgaagaacatgacaggtctggttgagatgtatggtaagaatgcacatctcagggatttggcaaaccttgtgattgtttgtggtgaccacggcaatcagtccaaggacagggaggagcaggctgagttcaagaagatgtacggtctcattgaccagtacaagttgaaggggcatatccgctggatctcagctcagatgaaccgtgttcgtaacggggagttgtaccgatacatttgtgacaccaagggagtctttgtccagcctgcattctatgaagcgtttggtctgactgtcatcgaagccatgacatgtggtttgccaacaatcgcaacatgccatggtggccctgctgagattattgttgatggggtgtctggtctgcacattgatccttaccacagtgacaaggctgctgatatcttggtcaacttctttgagaagtgcaagcaggattcaacctactgggacaatatttcacagggaggtctgcagaggatttacgagaagtacacctggaagctgtactctgagaggctgatgaccttgactggtgtatacggattctggaagtacgtaagcaaccttgagaggcgcgagactcgccgttacattgagatgttctatgctctgaaataccgcagcctggccagcgccgtcccattggctgtcgatggagagagcacatccaagtaa</cdnaseq>
Protein Sequence	<aaseq>MAAKLARLHSLRERLGATFSSHPNELIALFSRYVNQGKGMLQRH QLLAEFDALIEADKEKYAPFEDILRAAQEAIVLPPWVALAIRPRPGVWDYIRVNVSEL AVEELSVSEYLAFKEQLVDGHTNSNFVLELDFEPFNASFPRPSMSKSIGNGVQFLNRH LSSKLFQDKESLYPLLNFLKAHNHKGTTMMLNDRIQSLRGLQSSLRKAEEYLMGIPQD TPYSEFNHRFQELGLEKGWGDCAKRVLDTIHLLLDLLEAPDPANLEKFLGTIPMMFNV VILSPHGYFAQSNVLGYPDTGGQVVYILDQVRALENEMLLRIKQQGLDITPKILIVTR LLPDAVGTTCGQRVEKVIGTEHTDILRVPFRSENGILRKWISRFDVWPFLETYTEDVA NEIMREMQAKPDLIIGNYSDGNLVATLLAHKLGVTQCTIAHALEKTKYPNSDIYLDKF DSQYHFSCQFTADLIAMNHTDFIITSTFQEIAGSKDTVGQYESHIAFTLPGLYRVVHG IDVFDPKFNIVSPGADMSVYFPYTEADKRLTAFHPEIEELLYSEVENDEHKFVLKDKN KPIIFSMARLDRVKNMTGLVEMYGKNAHLRDLANLVIVCGDHGNQSKDREEQAEFKKM YGLIDQYKLKGHIRWISAQMNRVRNGELYRYICDTKGVFVQPAFYEAFGLTVIEAMTC GLPTIATCHGGPAEIIVDGVSGLHIDPYHSDKAADILVNFFEKCKQDSTYWDNISQGG LQRIYEKYTWKLYSERLMTLTGVYGFWKYVSNLERRETRRYIEMFYALKYRSLASAVP LAVDGESTSK</aaseq>
Gene Sequence	<dnaseqindica>5568..5615#5332..5470#4976..5220#4527..4845#3963..4187#3708..3874#3509..3625#3251..3424#3059..3154#2760..2976#2546..2664#2204..2396#1969..2120#1759..1879#1253..1347#aactatttattggtccttctggatctcggagaaaccctccattcgtttgctcgtctctgaccaccattgggtatgttgcttccattgccaaactgttcccttttacccataggctgattgatcttggctgtgtgattttttgcttgggtttttgagctgattcagcggcgcttgcagcctcttgatcgtggtcttggctcgcccatttcttgcgattctttggtgggtcgtcagctgaatcttgcaggagtttttgctgacatgttcttgggtttactgctttcggtaaatctgaaccaagaggggggtttctgctgcagtttagtgggtttactatgagcggattcggggtttcgaggaaaaccggcaaaaaacctcaaatcctcgacctttagttttgctgccacgttgctccgccccattgcagagttctttttgcccccaaatttttttttacttggtgcagtaagaatcgcgcctcagtgattttctcgactcgtagtccgttgatactgtgtcttgcttatcacttgttctgcttaatcttttttgcttcctgaggaatgtcttggtgcctgtcggtggatggcgaaccaaaaatgaagggttttttttttttgaactgagaaaaatctttgggtttttggttggattctttcatggagtcgcgaccttccgtattcttctctttgatctccccgcttgcggattcataatattcggaacttcatgttggctctgcttaatctgtagccaaatcttcatatctccagggatctttcgctctgtcctatcggatttaggaattaggatctaactggtgctaatactaaagggtaatttggaaccatgccattataattttgcaaagtttgagatatgccatcggtatctcaatgatacttactaaaacccaacaaatccatttgataaagctggttcttttatccctttgaaaacattgtcagagtatattggttcaggttgatttattttgaatcagtactcgcactctgcttcgtaaaccatagatgctttcagttgtgtagatgaaacagctgtttttagttatgttttgatcttccaatgcttttgtgtgatgttattagtgttgatttagcatggctttcctgttcagagatagtcttgcaatgcttagtgatggctgttgactaattattcttgtgcaagtgagtggttttggtacgtgttgctaagtgtaacctttctttgcagttcctgaaattgagtcatggctgccaagctagctcgcctccacagtctccgcgaacgcctcggtgccaccttctcgtctcatcccaatgagttgattgcactcttctctaggtgaagatctcaatataatatcttgtgtcttcttggaacctgctactaattgttttgagttttcaatgattttatccatacagttggttagttcttagtcaacccagatgtgaaacgataacatgttagtatgttacaaattcttagctgacaaggttatgcatctctttagttttaatgatggtatctataataatctgtgatgagctctaacatttttgtcttgagtcatgaatcttagatgatgttgaaatattgtttgttcatagctagattaagtacagatcatgtggtcttaaaaataagaagtaaaaatcaggtttatgtggtagtgccattaacatagttcagccgcagaaaggatgtgagatctaagcattggttctatttcttaaatatcactctatgcaggtatgttaaccagggaaagggaatgctccagcgtcaccagctgcttgcggagttcgatgccttgatcgaagctgacaaagagaaatatgctccctttgaagacattctccgggctgctcaggtaaatttggcaatgagccaggatggttatgatagtcaactcaaagtcaaataccagtctttctaacttacttccttgactgtatgtaggaagccattgtgctgccgccctgggttgcactggccatcaggccaaggcctggtgtctgggactacattcgggtgaatgtaagtgagttggcagtggaagagctgagtgtttctgagtacttggcattcaaggaacagcttgttgatggacagtaagtaccagaacgacgatttgcagattataactgaagcaaaataacagtgactgaattttacttctgtttttcttaaacagcaccaacagcaactttgttcttgagcttgattttgagcccttcaatgcctccttcccgcgcccgtccatgtccaagtccatcggaaatggggtgcagttccttaaccgtcacctgtcgtccaagttgttccaggacaaggagagcctctaccccttgctgaacttcctgaaagcccataaccacaagggcacggtaagcttccaatttgtggaacataccaaatgcttttatactagatgttttttcttgtgtgaattgctttaaatgttagtcctttagaaacccacttgacattctctgtaagttccaccaaatgacgggatccgaattttctattacagacaatgatgctgaatgacagaattcagagccttcgtgggctccaatcatcccttagaaaggcagaagaatatctgatgggcattcctcaagacacgccctactcggagttcaaccacaggtgattactttattatttctccttatcatatagcccatgttatactactgcaaatggaataattccttacaatgtgattcatgatttgaatacaggttccaagagctcggtttggagaagggttggggtgactgtgcaaagcgtgtgcttgacaccatccacttgcttcttgaccttcttgaggcccctgatccggccaacttggagaagttccttggaactattccaatgatgttcaatgttgttatcctgtctccgcatggatactttgcccaatccaatgtgttgggataccctgatactggtggtcaggtagagctttttaacaaattttccccttatatacagtacttcaaatatttctagttttgacctgttattctgttgtttgcaggttgtgtacattttggaccaagtccgcgctttggagaatgagatgcttttgaggatcaagcagcaaggccttgatatcacacctaagatcctcattgtatgttcaagatgttggtcttgaatgtttcaagttttaaacacttctcagtgcgaattgtagagtaacgtgcggacatgattttacttgatgcaggtaaccaggctgttgcctgatgctgttggtactacatgcggccagcgtgtggagaaggttattggaactgagcacactgacattcttcgtgttccattcaggagtgagaatggtatcctccgcaagtggatctcccgttttgatgtctggccattcctggaaacatacactgaggtaaatggtttatctgacaacgtccttcagagctgagcacaaaccatgaattctgagagctcatctttttttttttggttgcaggatgttgcaaacgaaattatgagggaaatgcaagccaaacctgatctcatcattggcaattacagtgatggaaaccttgttgccactctgctggctcacaaattaggagttacccaggtatgtttggttgtaaaccactcctttaaatatttctttcattaagtcaattacttatgatttctcttctacatggatacagtgtaccattgctcatgccttggagaaaaccaaataccccaactcagacatatacttggacaagtttgacagccagtaccacttctcatgccaattcactgctgatcttatcgccatgaatcacactgatttcatcatcaccagtacattccaagaaattgctggaaggtaaaattttctaaagagcagtagaatattgctgcgttgtgccaacacctaaacgggtatctgatgtttgtttcctctgtttcttcagcaaggacactgtggggcagtatgaatcacacattgcattcacccttcctgggctttaccgagttgtgcatggcatagatgtttttgatcccaagttcaacattgtctctcctggagctgacatgagtgtctacttcccgtacaccgaggctgacaagaggctcactgctttccaccctgaaattgaggagcttctctacagtgaagtcgagaacgatgaacacaagtgagtactgaactgctggttccgtccctgttattcacctaccatgtaacaaataattaaacactgatttgtgtgtttggtctagctttggctcttcagtctactaagtgccatgcactagaactttgtagatttgaactgcaattcttaattttctcactccttagtagaccacaataataattattgtgtctgacccagctagtttacaatagtgacttcaatgcttgttttttccccttgaacaattgtttactttctagcagtggagtttggcatctaaacttgaatacacgctgttcttttttgtgtataaaatgtttatttaatgttctgcaggtttgtattgaaggacaagaacaagccaatcatcttctccatggctcgtcttgaccgagtgaagaacatgacaggtctggttgagatgtatggtaagaatgcacatctcagggatttggcaaaccttgtgattgtttgtggtgaccacggcaatcagtccaaggacagggaggagcaggctgagttcaagaagatgtacggtctcattgaccagtacaagttgaaggggcatatccgctggatctcagctcagatgaaccgtgttcgtaacggggagttgtaccgatacatttgtgacaccaagggagtctttgtccaggtatatacatacgctgtcatattctactgctatatttctattctgagcttccagtagcaaatgatttctactatttgtaaagaacagccttgtgcttgagactaaaactgcttttaaaattgttttttagcctgcattctatgaagcgtttggtctgactgtcatcgaagccatgacatgtggtttgccaacaatcgcaacatgccatggtggccctgctgagattattgttgatggggtgtctggtctgcacattgatccttaccacagtgacaaggctgctgatatcttggtcaacttctttgagaagtgcaagcaggattcaacctactgggacaatatttcacagggaggtctgcagaggatttacgagaagtatgtatttcatgatctgcaaatatataacattttttttttacgattgacatataactgtagaaatcatgtgtccaatctatattgatcctacaaatttggacttgtcaggtacacctggaagctgtactctgagaggctgatgaccttgactggtgtatacggattctggaagtacgtaagcaaccttgagaggcgcgagactcgccgttacattgagatgttctatgctctgaaataccgcagcctggtaagttactctcgctgttcaacagcttgttaatttcagtattattgcactgagcatatctctgaattctgttgctacatttctttgttgaatccaggccagcgccgtcccattggctgtcgatggagagagcacatccaagtaatggaggggaaaatatgcatcttcagcaggagaagccgtcagctgcattcgaatttgataattttctgtagttgtcatttggcatccatgtttgccatggatgtgtactatgtctaaggtttcagtacttttgcgagattttgggcagtgcttgcctcaaataaacgccggttcctggtgtttatcgttcagaattcaatgcaatgttttattgccgcgcttcctcaatctgtcatgttgaatgaccactccctagtgccctactgtt</dnaseqindica>
External Link(s)	NCBI Gene:Os06g0194900, RefSeq:Os06g0194900