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81.
被毛突变无毛小鼠皮肤及毛结构观察 总被引:6,自引:1,他引:5
对国内首次发现并培育成群的BALB/c突变小鼠的3种表型(无毛、全毛、中间态)的皮肤组织及毛结构进行了观察。结果表明,无毛小鼠仅具有非常短(1~2mm)、细且弯曲的绒毛,其毛于中心为空泡状,缺乏髓质。无毛小鼠表皮、真皮、皮下组织结构基本与全毛、中间态小鼠相同,但其毛生长周期不健全;毛球位置浅表,数目少,排列不规则;皮脂腺异常增生。推测其被毛结构异常是由毛自身结构异常所致。该小鼠外观似裸鼠,能在普通条件下生长繁殖,可望成为某些皮肤病等研究的动物模型。 相似文献
82.
采用MAMA-PCR法对72株已知突变菌株的突变情况进行了检测。结果,有2种gyrA83位突变:TCG→TTG和TCG缺失;4种gyrA87位突变:GAC→AAC、GAC→GGC、GAC→TAC和GAC→CAC;1种parC80位突变:AGC→ATC以及4种parC84位突变:GAA→AAA、GAA→GCA、GAA→GGA和GAA→GTA。采用同样的方法,对38株未知突变菌株的检测结果显示,gyrA83、gyrA87、parC 80和parC84位的突变检出的正确率分别为97.4%、94.7%、81.6%和94.7%。结果表明,MAMA-PCR有望成为监测耐氟喹诺酮类药物大肠埃希氏菌的分子生物学常规方法。 相似文献
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84.
HU Bin ZENG Bing-hui HU Yue-lin ZHAO Qiang JING Xiang-yi ZHANG Yong-ling WANG Yi-ming 《园艺学报》2015,31(7):1237-1241
AIM: To investigate the underlying genetic changes of a Chinese patient with infantile malignant osteopetrosis (IMO). IMO is a monogenic disease, mostly caused by mutations of TCIRG1 and CLCN7 genes. The former is believed a homozygous gene and only cause the disease in homozygous or compound heterozygous status. However, it has been reported that heterozygous mutations also cause the disease in 6 non-Chinese cases. METHODS: Genomic DNA was extracted from peripheral blood of the patient and his parents. All exons and splice sites of TCIRG1 and CLCN7 genes were amplified by PCR followed by Sanger sequencing. Mutation detection in the 2 genes was also investigated in the parents. Haplotypes were constructed by variations obtained in mutation detection and microsatillites flanking TCIRG1 gene in the family by Cyrillic. Chromosomal microarray analysis (CMA) was performed to detect copy number variations (CNV) of the patient and his mother. RESULTS: A novel mutation c.449_452delAGAG (p.Gln149Glnfs16) was detected in the patient. This mutation truncated 666 amino acids at the C terminal of the V-ATPase 116 kD isoform a3 protein. It wiped out the entire ATPase V0 complex and was predicted to result in total loss of protein function. This mutation was also detected in the patient's father. No pathogenic mutation was detected in CLCN7 gene. CMA did not reveal any CNV involving TCIRG1 or CLCN7 gene. CONCLUSION: We reported a novel heterozygous mutation of TCIRG1 gene causing IMO. This represents the first IMO case in China caused by heterozygous TCIRG1 gene mutation. 相似文献
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Eleven interspecific hybrids of cassava with the wild relatives Manihot glaziovii, M. pseudoglaziovii. M. dichotoma and M. anomala were examined to detect unreduced microspores. The frequency of dyads and triads was counted, as well as pollen viability. Of these hybrids, the second generation progeny of cassava×M. glaziovii showed a high frequency of unreduced microspores (3.7%) permitting their selection for further manipulation of this character. An association of vegetatively-reproduced genotypes and the occurrence of unreduced microspores has also been observed. 相似文献
88.
Summary A giabrous mutant was identified from progenies of chickpea seeds that were treated with ethyl methane sulphonate (EMS). The mutant has no shoot hairs in contrast to the dense hairs on normal chickpeas. The character is governed by a single recessive gene. This mutant can be useful in certain pathological and eniomological studies. 相似文献
89.
Summary Developmental stages during gametogenesis of rice were histologically examined in the period from differentiation of reproductive organs to anthesis. Plants were exposed to acute X-rays of 20 Gy. Radiosensitivity and mutation frequency were investigated in relation to the developmental stages of reproductive organs. The most radiosensitive stage, as measured by reduction of the M1 pollen-and seed-fertilities, was the last premeiotic interphase. Mutations induced at different developmental stages were scored in M3 strains. Sterility mutants and short-culm mutants were most frequently observed. Grain shape, panicle morphology, heading-date and endosperm character mutants were induced at a relatively low frequency. The overall mutation frequency varied with the developmental stage at the time of irradiation. The highest overall mutation frequency was observed when radiation was applied 10 days before anthesis, the late tetrad stage of microspores. Radiation exposure of florets at the late tetrad stage was found to be a more efficient method of inducing a large number of mutations than radiations applied to seeds and fertilized egg cells. 相似文献
90.
Brian P. Forster 《Euphytica》2001,120(3):317-328
A review of research at the Scottish Crop Research Institute (SCRI) on the effects of semi-dwarfing genes on salt tolerance
in barley is given. Work began in1993 with the fortuitous and unexpected result that the cultivar ‘Golden Promise’ showed
considerable tolerance to salt. Golden Promise is a gamma-ray induced semi-dwarf mutant of the cultivar ‘Maythorpe’. The parent
and mutant cultivars are presumed to be isogenic, but show significant differences in their responses to salt stress. The
positive and pleiotropic effects of the mutant gene, commonly known as GPert were found to be effective in a number of genetic backgrounds. Earlier, in 1991 Frackowiak showed that the GPert mutation was allelic to the ari-e mutants in barley. The ari-emutants were salt tested and found to show the same positive responses to salt stress as Golden Promise. This supported the
allelism tests, and consequently the GPert symbol was changed to ari-e.GP. The semi-dwarf mutant sdw1 (also known as denso) and the erectoides semi-dwarf mutant,ert-k
32 were also tested for their effects on tolerance to salt, but did not show any positive effects. Salt tolerance was therefore
not a general phenomenon of semi-dwarf stature but specific to mutations at the Ari-e locus in these lines. Genetic markers (RAPDs, AFLPs and SSRs) have been used for fingerprinting, genetic mapping, and QTL
analysis. The markers have helped 1) confirm the isogenic relationship between Maythorpe and Golden Promise, 2)clarify the
confusion over the pedigree of Golden Promise, and 3) genetically map the ari-e.GPlocus and examine its pleiotropic effects.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献