| Cotton is an important ecomonic crop in the world. Transgenic cotton has played anmore and more important role in cotton breeding and practice. Pollen tube pathway hasbeen one of key ways to transformation for cotton, in China, upto now about 40%transgenic cotton varieties are from plasm by pollen tube pathway directely or indirectly.There is little system research report about the intergration mechanism of poll tubepathway, the distribution of foreign gene in recipicent parents and the effects of foreigngenes' integration on recipicent. In this study, a set of 30 different transgenic lines fromthe same recipient were used as basic materials. Flanking sequences were cloned ingenomic walking PCR, and the feature of integration were analyzed by comparing amongthe obstained sequence; based on the difference in phenotype for mian traits under 2enviroments, transgenic lines were analyzed and clusterd; and two transgenic lines andtheir recipient were chosed for analysis about difference of gene expressions, and fordissection of genetic effects in two environment by mAD model. The main results were asfollows:A cloning system about flanking sequence of foreign gene in transgenic cotton bypollen tube pathway were built on the basis of genomic walking PCR. 9 sequences werecloned by genomic walking PCR in 12 transgenic lines, among which 5 were vectorsequce totally, and 4 contained nknown sequences. The effiency for sequence cloningwere 33.3%.The results of comparing the obstained sequence with the vector by DNAMANshowed that when foreign gene inserted into the recipient genome, it took more vecorsequence with it, not exact the sequence between left border and right boder. Somesequences in foreign gene express cassette (such as, partial sequence of 35S promoter orGUS) or in vector (such as OriV) appeared in the flanking sequence. The Blast in internetfor 4 obstained unkown sequence supported the conclusion that 3 were in genic and 1 inintergenic.The integration of foreign gene caused obvious phenotype changes for traits inrecipients, and the changes were not correlated with the kind of foreign gene. On the whole, transgenic had little effects on the fiber quality traits, and had important effects onyield and its components. Most transgenic lines (90%)had the similar change, whichwere singnificant or extremely singnificant reduced boll weight; 46.7% transgenic lineshad little changed on lint percentage, and 20% increased lint percentage singnificnatlyor extremely singnificantly and 33.3% reduced singnificantly.In homozygous condition, 2 transgenic lines had higher ratios of gene differentialexpression than their recipient, indicating that the integration of foreign gene can increasethe amount of gene expression, but it were not always higher than recipient at anydevelopment stage. The ratios were higher in transgenic lines than in recipient on July 1and on July 15, while they were lower on June 15 and August 1.In heterozygous condition, the amount of total repeatable bands was higer than that inhomozygous condition, and the amount of differential bands was higher too, but the radioof gene differential expression were lower. 2 transgenic lines had the similar change ofratio, which were the ratios of transgenic lines in heterozygous condition were lower thanthat in homozygous.The genetic effects of dQTL in transgenic lines were dissected from the geneticbackground into additive effects and dominance effects by modified AD model. The resultshowed that the dQT1 in 439030 increased the lint percentage, boll weight and bollnumber. The dominance effects of dQTL were also predicted in homozygous condition andheterozygous condition.These results will provide some academic refrences in the field of foreign geneintegration by pollen tube pathay, the effect of integration on recipients and so on, and thegene differential expression between transgenic lines and their recipient parents were firstreported, and it was new attempt to predict the genetic effects for dQTL in transgeniclines using modified AD.
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