CAJ | 학술논문

陆地棉李氏超短纤维突变体(Li_1li_1)是显性单基因突变体,表现为茎秆、叶片卷曲,纤维短至6 mm,其隐性纯合体(li_1li_1)则表现为株型和纤维发育都正常.对开花后10d的李氏纤维发育正常材料(li_1li_1)和超短纤维突变体(Li_1li_1)胚珠纤维混合体进行mRNA差异显示反转录PCR(DDRT-PCR)分析,获得1条在李氏纤维发育正常材料中上调表达的差异片段.进一步通过5'RACE技术获得全长为621 bp的cDNA,测序及DNA序列的生物信息学分析表明该cDNA片段与拟南芥编码阿拉伯半乳糖蛋白基因AGP14有52%相似性,故命名为GhAGP.表达特征分析表明.该基因在陆地棉根、茎、叶和纤维中组成性表达,在棉纤维中优势表达.基因组序列分析显示.该基因在二倍体棉种非洲棉和雷蒙德氏棉中各有1个拷贝,在四倍体棉种陆地棉TM-1和海岛棉海7124中分别存在2个拷贝,表明A、D亚组中各有1个拷贝.利用本实验室陆地棉遗传标准系TM=1和海岛棉海7124培育的含140个单株的BC_1作图群体,将GhAGP基因的2个拷贝分别定位在四倍体棉花部分同源转化群染色体6和染色体25上.
륙지면리씨초단섬유돌변체(Li_1li_1)시현성단기인돌변체,표현위경간、협편권곡,섬유단지6 mm,기은성순합체(li_1li_1)칙표현위주형화섬유발육도정상.대개화후10d적리씨섬유발육정상재료(li_1li_1)화초단섬유돌변체(Li_1li_1)배주섬유혼합체진행mRNA차이현시반전록PCR(DDRT-PCR)분석,획득1조재리씨섬유발육정상재료중상조표체적차이편단.진일보통과5'RACE기술획득전장위621 bp적cDNA,측서급DNA서렬적생물신식학분석표명해cDNA편단여의남개편마아랍백반유당단백기인AGP14유52%상사성,고명명위GhAGP.표체특정분석표명.해기인재륙지면근、경、협화섬유중조성성표체,재면섬유중우세표체.기인조서렬분석현시.해기인재이배체면충비주면화뢰몽덕씨면중각유1개고패,재사배체면충륙지면TM-1화해도면해7124중분별존재2개고패,표명A、D아조중각유1개고패.이용본실험실륙지면유전표준계TM=1화해도면해7124배육적함140개단주적BC_1작도군체,장GhAGP기인적2개고패분별정위재사배체면화부분동원전화군염색체6화염색체25상.
The Ligon lintless mutant (Li_1li_1) is a fiber elongation developmental mutant with a dominant monogenetic mutation characterized by short fibers and distorted leaf, stem and flower growth, and the recessive pure line (li_1li_1) exhibits normal fiber developmental characteristics. The objectives of this study were to isolate genes preferentially or specifically expressed in fiber elongation stage by comparing gene expression differences between Li_1li_1 and li_1li_1. RNA isolated from 10 days post anthesis (DPA) fibers and owles mixture in Li_1li_1 and li_1li_1 were used to screen differential gene expression in fiber development using differential display reverse transcriptase polymerase chain reaction (DDRT-PCR). One differential expression cDNA segment was isolated and the corresponding full-length cDNA was cloned by 5' RACE method. Sequencing and bioinformatics analysis showed the protein had 52% homology with arabinogalactan protein from Arobidopsis, therefore, this gene was temporarily des-ignated GhAGP. RT-PCR and quantitative real time RT-PCR assays all indicated that the transcript of GhAGP is constitutively expressed in root, stem, leaf and fiber, with higher expression levels in fiber cells as fiber developments. Genomic sequence analysis showed there was one copy of GhAGP in diploid cotton species, G. herbaceum and G. raimondii, and two copies in te-traploid cotton species, G. hirsutum and G. barbadense respectively, indicating that the sub-genome A and sub-genome D con-tain each of them. Using the BCi mapping population derived from the hybridization between the upland cotton standard line TM-1 and G. barbadense cultivar Hai7124, and TM-1 as recurrent parent, two copies of GhAGP were located on the homoelo-gous chromosomes 6 and 25, respectively.