微卫星标记对WHBE兔封闭群、日本大耳白兔和新西兰兔的遗传分析

目的分析比较大耳白黑眼兔（WHBE兔）封闭群与日本大耳白兔（Jw兔）、新西兰兔（NZW兔）基因组存在的微卫星结构,研究WHBE兔封闭群的微卫星多态性。方法利用21个微卫星位点,通过微卫星分子标记技术对WHBE兔封闭群、Jw兔和NZW兔进行遗传多样性检测和对比。结果根据初步结果,在21对微卫星引物中筛选出扩增产物稳定并且具有多态性的11对引物。WHBE兔封闭群在每个位点上的等位基因数为3～8个不等,11个位点的平均有效等位基因数为2．0402个,平均杂合度为0．4810;Jw兔在每个位点上的等位基因数为2～8个不等,11个位点的平均有效等位基因数为3．6077个,平均杂合度为0．5039;NZW兔在每个位点上的等位基因数为3～9个不等,11个位点的平均有效等位基因数为2．6537个,平均杂合度为0．5334。WHBE兔封闭群在11个微卫星位点上的平均多态信息含量（PIC）为0．6005,多位点累积个体识别率达到100％,多位点累积非父排除概率（CPE）在双亲信息都是未知情况下的为0．9613,而在得知任一亲本信息的情况下,CPE值高达0．9973。在11个微卫星座位中,9个位点上出现了WHBE兔封闭群特有等位基因,其中在Sat2、Sat5、Sat7、Sat12、Sat13、Sat16、S0144和INRACCDDV0003八个位点上WHBE兔封闭群的特有等位基因为一个,在sat8位点上为两个。结论WHBE兔8个位点的平均杂合度、平均有效等位基因数均比JW兔及NZW兔低,说明WHBE兔群体的基因纯合度高于其他两个品系,具有更优的遗传稳定性。9个WHBE兔特有的等位基因可作为区分WHBE兔封闭群和其它两个品系实验兔的分子标记。     

Rabbit muscle gangliosides

Four ganglioside fractions were isolated from rabbit muscle: one hematoside and three hexosamine-containing species. They were analyzed for hexoses, hexosamine, sialic acid, fatty acids, and long-chain base content. The molar ratios of sphingosine-hexose-hexosamine-sialic acid were: for hematoside, 1:2:0:1; for the disialogangliosides, 1:3:1:2; and for trisialoganglioside, 1:3:1:3. The carbohydrates were studied by thin-layer and paper chromatography. The hexoses were glucose and galactose; the hexosamine was N-acetylgalactosamine and the sialic acid was N-acetylneuraminic acid. Fatty acids and long-chain bases were analyzed by gas-liquid chromatography. The fatty acid composition was similar in all of the four gangliosides. The most abundant fatty acids were 16:0 and 18:0, but significant amounts of 16:1, 18:1, 20:0, and 22:0 were also found. Hydroxy fatty acids were not detected. In all of the muscle gangliosides the main long-chain bases were C(18)-sphingenine and C(20)-sphingenine. In hematoside there were also measurable amounts of C(18)-sphinganine and C(20)-sphinganine, whereas in the major gangliosides only traces of C(18)-sphinganine were detected.     

Rabbit encephalitozoonosis in Kenya.

Encephalitozoon cuniculi infection was diagnosed in a laboratory rabbit breeding colony at Muguga, Kenya. This is the first report of the disease in rabbits in Kenya. Post-mortem examination showed gross renal lesions and the presence of the parasite in histological sections of the cerebrum and cerebellum. On Gram stain, spores were observed in the kidney sections.     

Translation of Rabbit Globin mRNA

IN certain conditions bacterial initiation factors can discriminate between different classes of mRNA, or the individual cistrons of bacteriophage RNA^1–5. Whether messenger specificity is a general phenomenon in eukaryotes as well is controversial, but several reports support the idea that mRNAs can be translated in heterologous systems without the addition of homologous tissue-specific factors, suggesting a lack of specificity^6,10,17. These results have been obtained by adding mRNA either to oocytes⁷ or to crude cell-free systems such as lysates or 30,000g supernatants (S-30). With more fractionated systems—separated ribosomes reconstituted with cell sap—the existence of messenger specific factors is supported^11–13. We have already demonstrated that an S-30 derived from either mouse or rat liver can faithfully translate rabbit globin mRNA without the addition of reticulocyte factors and now report that fractionation of this S-30 using methods similar to those used by previous workers^11–13 results in a system which will also translate globin mRNA. This fractionated system does not show a requirement for reticulocyte specific factors.     

Experimental Osteoarthritis in the Rabbit

Based on an experimental model of osteoarthritis in 42 full-grown rabbits the histological changes were studied during the development of osteoarthritis after operative induction of instability of the knee joint. The changes were followed from 2 week to 1½ years after the induction. The first changes were observed at 1 week stage as a proliferation of the lining cells. During the time of observation additional changes were seen such as hypertrophy of villi, infiltrations with plasma cells and lymphocytes, increased vascularity and interstitial edema and fibrosis. Edema was only seen during the first months, later increasing fibrosis was predominant. The first cartilage change was reduction of the staining ability, expressing depletion of GAG, this was seen already at the one week stage whereas morphological changes were present after 4–6 weeks. It was concluded that the synovial membrane in this model shows changes that may contribute to the development of osteoarthritis.     

Rabbit liver acetyl-CoA synthetase.

Acetyl-CoA synthetase (EC 6.2.1.1) was assayed in subcellular fractions of rabbit liver homogenates. The activity was located almost exclusively in the cytosol. There was no decrease in activity when butyrate or propionate (each at 5--20 mM) were added to the assay medium.     

Somatic Chromosomes of the Rabbit

The number of chromosomes of the rabbit was determined at 44, and both the X and the Y chromosomes have submedially situated centromeres. X is of medium size while Y is one of the smallest chromosomes of the complement. For practical purposes, the chromosomes have been divided into groups according to their appearance.