A CHASE domain containing protein kinase OsCRL4, represents a new AtCRE1-like gene family in rice

AtCRE1 is known to be a cytokinin receptor in Arabidopsis. The AtCRE1 protein contains CHASE domain at the N-terminal part, followed by a transmitter (histidine kinase) domain and two receiver domains. The N-terminal CHASE domain of AtCRE1 contains putative recognition sites for cytokinin. Five CHASE domains containing proteins were found in rice, OsCRL1a, OsCRL1b, OsCRL2, OsCRL3, and OsCRL4. OsCRL1a, OsCRL1b, OsCRL2 and OsCRL3 contain the four domains existing in CRE1, whereas OsCRL4 only contains the CHASE domain and a putative Ser/Thr protein kinase domain. The authors cloned the encoding gene OsCRL4 and found that it represents a new member of the cytokinin receptor protein in rice.     

A CHASE domain containing protein kinaseOsCRL4, represents a newAtCRE1-like gene family in rice

AtCRE1 is known to be a cytokinin receptor inArabidopsis. TheAtCRE1 protein contains CHASE domain at the N-terminal part, followed by a transmitter (histidine kinase) domain and two receiver domains. The N-terminal CHASE domain ofAtCRE1 contains putative recognition sites for cytokinin. Five CHASE domains containing proteins were found in rice,osCRL1a,OsCRL1b,OsCRL2,OsCRL3, andOsCRL4.OsCRL1a,OsCRL1b,OsCRL2 andOsCRL3 contain the four domains existing inCRE1, whereasOsCRL4 only contains the CHASE domain and a putative Ser/Thr protein kinase domain. The authors cloned the encoding geneOsCRL4 and found that it represents a new member of the cytokinin receptor protein in rice. Project supported by the National Natural Science Foundation of China     

Production of bacterial blight resistant lines from somatic hybridization between Oryza sativa L.and Oryza meyeriana L.

Novel bacterial blight (BB) resistance gene(s) for rice was (were) introduced into a cultivated japonica rice variety Oryza sativa (cv. 8411), via somatic hybridization using the wild rice Oryza meyeriana as the donor of the resistance gene(s). Twenty-nine progenies of somatically hybridized plants were obtained. Seven somatically hybridized plants and their parents were used for AFLP (amplified fragment length polymorphism) analysis using 8 primer pairs. Results confirmed that these plants were somatic hybrids containing the characteristic bands of both parents. The morphology of the regenerated rice showed characters of both O. sativa and O. meyeriana. Two somatic hybrids showed highest BB resistance and the other 8 plants showed moderate resistance. The new germplasms with highest resistance have been used in the rice bfeeding program for the improvement of bacterial blight resistance.     

Production of bacterial blight resistant lines from somatic hybridization between Oryza sativa L. and Oryza meyeriana L.

Novel bacterial blight (BB) resistance gene(s) for rice was (were) introduced into a cultivated japonica rice variety Oryza sativa (cv. 8411), via somatic hybridization using the wild rice Oryza meyeriana as the donor of the resistance gene(s). Twenty-nine progenies of somatically hybridized plants were obtained. Seven somatically hybridized plants and their parents were used for AFLP (amplified fragment length polymorphism) analysis using 8 primer pairs. Results confirmed that these plants were somatic hybrids containing the characteristic bands of both parents. The morphology of the regenerated rice showed characters of both O. sativa and O. meyeriana. Two somatic hybrids showed highest BB resistance and the other 8 plants showed moderate resistance. The new germplasms with highest resistance have been used in the rice breeding program for the improvement of bacterial blight resistance.     

A new genetic factor for root gravitropism in rice (Oryza sativa L.)

Root gravitropism is one of the important factors to determine root architecture. To understand the mechanism un-derlying root gravitropism, we isolated a rice (Xiushui63) mutant defective in root gravitropism, designated as glsl. Vertical sections of root caps revealed that glsl mutant displayed normal distribution of amyloplast in the columella cells compared with the wild type. The glsl mutant was less sensitive to 2,4-dichlorophenoxyacetic acid (2,4-D) and a-naphthaleneacetic acid (NAA) than the wild type. Genetic analysis indicated that the phenotype of glsl mutant was caused by a single recessive mutation, which is mapped in a 255-kb region between RM16253 and CAPSI on the short arm of chromosome 4.     

Seminal, adventitious and lateral root growth and physiological responses in rice to upland conditions

INTRODUCTIONOryzasativaL .riceisasemi aquaticspe ciesadaptedtoavarietyofclimates.Uplandricedependsmainlyonrainfall,isoftenexposedtodrought,andhasdevelopeddroughtresistanttraits.Aprincipalmechanismbywhichriceadaptstowaterdeficiencyisthroughtheposses sionof…     

水稻微卫星标记的研究进展

微卫星又称简单重复序列,是一类由几个核苷酸(一般1～6个)为重复单元而形成的串联重复序列.由于它具有含量丰富、多态性高、共显性和检测方法简单等优点,而广泛应用于品种鉴定、种质资源保护、遗传作图、基因定位和QTL分析等方面.文章就微卫星标记在水稻中的开发和应用进展作一概述.     

水稻RILs化感作用遗传模型分析

本研究以Lemont（弱化感）和Dular（强化感）水稻杂交产生的重组自交系（recombinent inbred lines,RILs）及其亲本为供体植物,并以稻田主要杂草稗草为受体植物,采用迟播共培法对群体及亲本化感作用进行测定及评价,应用主基因＋多基因分离分析法研究水稻化感作用的遗传体系。结果表明,水稻亲本化感抑草作用差异较大,对受体稗草的根长抑制率呈连续变异,体现出数量性状特征;水稻Lemont（弱化感）×Dular（强化感）组合的Rlhs群体化感作用遗传体系由两对连锁的主基因控制,主基因间的作用方式呈互补作用。进一步估计受体根长抑制率的遗传参数,结果表明,稗草根长抑制率的群体均值m=29．3908245,主基因加性效应与加性×加性上位性互作效应I^＊=7．0619195,主基因遗传率为49．36379％．     

发育中水稻种子淀粉合成分子机制的研究

对GenBank中9215条来源于水稻(Oryza sativa L.ssp．Indica)胚乳cDNA库的3’EST进行了分析,获得20个淀粉合成相关基因的表达丰度信息,研究发现淀粉合成的5个关键酶的编码基因,ADPG焦磷酸化酶基因、ADP—葡萄糖淀粉合成酶、淀粉分支酶、淀粉去分支酶、蜡质基因的表达丰度极高,表明该时期水稻胚乳内淀粉合成反应非常强烈,研究发现在淀粉合成途径中存在功能相关的基因协同表达的现象,章结合所获得的基因表达信息对淀粉合成的分子机理进行了探讨。     

水稻穗内不同粒位间的矿质营养变化差异及其与籽粒植酸含量的关系

研究目的：阐明水稻穗内不同粒位间的主要矿质营养元素和植酸含量差异、粒位分布特点及其与品种穗型间的联系。创新要点：将水稻品种的穗型变化与稻米营养品质结合起来,从水稻穗粒结构角度,对同一稻穗内不同籽粒间的主要矿质营养元素与植酸含量差异、粒位分布特点及其与水稻品种穗型间的相互关系进行了较系统的探讨分析。研究方法：以典型的直立穗型和弯穗型粳稻品种为材料,通过对两类水稻品种在相同栽培条件下籽粒矿质营养元素和植酸含量的测定分析,并依据水稻籽粒在稻穗上的着生部位,将同一稻穗内的不同籽粒划分为六个粒位,比较分析了两类品种同一稻穗内不同部位间矿质营养元素和植酸含量的差异变化及其粒位分布特点。重要结论：水稻穗型虽然与品种问的籽粒矿质营养元素和植酸含量高低没有直接关系,但对其穗内不同籽粒间的主要矿质营养元素和植酸含量存在着较大影响;与稻穗中下部的弱势粒相比,同一稻穗内着生在稻穗上中部的强势粒通常具有相对较高的锌、铁矿质元素含量,而籽粒植酸含量和植酸,锌（铁）摩尔比则有所降低,稻米营养品质也相对较好;不同矿质营养元素相比,粒位效应对铁矿质营养的影响作用要略大于对钙和锌营养元素含量。     

Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa

Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6-phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6-phosphate/phosphate translocator (GPT) was isolated from a cDNA library of immature seeds of rice and named as OsGPT. The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000-grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6-phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.     

水稻颖壳异常发育突变体Oryza sativa extraordinary glume 1(Oseg 1)的遗传与基因初定位分析(英文)

A rice mutant with Japonica 9522 cultivar background Oryza sativa extraordinary glume 1 (Oseg 1) was identified from the M2 mutant pool mutagenized by ~(60)Coγ-ray.Compared with wild type plants,Ose9 1 developed longer empty glumes and rudimentary glumes.In some Oseg 1 mutants,the number of stamens of flowers was reduced and leaf-like lodicules occurred,and excessive lemma/palea-like organ could be observed in some mutant spikelets.This indicated that OsEG1 could regulate the development of rudimentary glumes,empty glumes,lemma/palea,lodicules,and stamens.Genetic analysis indicated that Oseg 1 came from a single recessive genetic locus.To clone OsEG1 gene,F_2 population was constructed by a cross between Ose9 1(Japonica)and Guangluai4(Indica).Using map-based cloning approach,OsEG1 was mapped on chromosome 4,between INDEL marker OS407 and WHM0466 with genetic distance of 2.0 cm and 1.0 cm,respectively.These results are useful for further cloning and functional analysis of the OsEG1 gene.     

Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa

INTRODUCTIONNongreenplastidsofheterotrophictissuesarecarbohydrate importingorganellesand ,inthecaseofamyloplastsofstoragetissues,thesiteofstarchsynthesis.Investigationofwholetissuesfromavarietyofstarchsynthesizingcropplantsindicatedthathexoseunitswereimpo…     

水稻颖壳异常发育突变体Oryza sativa extraordinary glume 1 (Oseg 1) 的遗传与基因初定位分析

A rice mutant with Yaponica 9522 cultivar background Oryza sativa extraordinary glume 1 （Oseg 1） was identified from the M2 mutant pool mutagenized by ^60Co γ-ray. Compared with wild type plants, Oseg 1 developed longer empty glumes and rudimentary glumes. In some Oseg 1 mutants, the number of stamens of flowers was reduced and leaf-like lodicules occurred, and excessive lemma/palea-like organ could be observed in some mutant spikelets. This indicated that OsEG1 could regulate the development of rudimentary glumes, empty glumes, lemma/palea, lodicules, and stamens. Genetic analysis indicated that Oseg 1 came from a single recessive genetic locus. To clone OsEG1 gene, F2 population was constructed by a cross between Oseg 1 （Japonica） and Guangluai4 （Indica）. Using map-based cloning approach, OsEG1 was mapped on chromosome 4, between INDEL marker OS407 and WHM0466 with genetic distance of 2.0 cm and 1.0 cm, respectively. These results are useful for further cloning and functional analysis of the OsEG1 gene.