Structure, Behavior, and Gene Functions of Avian Sex Chromosomes

1997年，也就是长达3年的联合研究的最后一年，H.Macgregor教授于10月1日和2日在英国莱斯特大学组织了一次关于禽类染色体分子细胞遗传学的研讨会，来自日本、英国、俄罗斯、法国和德国的约20名活跃在这一领域的科学家参加了会议，并介绍了他们的最新研究成果。S.Mizuno及其合作者(A.Ogawa，T.Hori，M.Teranishi和Y.Itoh)提出了以下结果：1)通过从雌性鸡基因组DNABAC文库中筛选克隆，从位于每条染色体的前减数分裂配对末端附近的基因组克隆开始，通过外显子捕获程序寻找基因，并通过荧光原位杂交(FISH)在鸡卵母细胞的Z-W二价体上定位克隆；2)在鸡Z染色体和雌性…的短臂中间发现雄性高甲基化(MHM)区域3)利用与鸡W染色体上EE0.6序列相关的性染色体特异序列的聚合酶链式反应(PCR)对东方白鹤进行性别鉴定；(4)用FISH技术结合3个基因组克隆，证明东方白鹤的性染色体对具有共同来源；Solovei与A.Ogawa和S.Mizuno的联合实验结果表明，鸡W染色体上的Xhol1和EcoRI家族重复序列在鸡的减数分裂前的W染色体上形成了各自特有的染色单体，染色单体的大小随其重复频率的变化而变化。S.Mizuno和合作研究人员在研讨会前访问了爱丁堡的罗斯林研究所，与大卫·伯特就鸡基因图谱项目进行了交谈。研讨会结束后，他们在H.Macgregor的实验室与I.Solovei进行了联合实验，并可以证明MHM区域位于鸡的灯刷W染色体上的特定环路中并被转录。较少

In 1997, the last year of the 3 years long joint research, Professor H.Macgregor organized a symposium on Molecular Cytogenetics of Avian Chromosomes, which was held on the 1st and 2nd October at the University of Leicester, U.K., where about 20 scientists actively working in this field attended from Japan, U.K., Russia, France and Germany and presented up-to-date results of their research. S.Mizuno and co-investigators (A.Ogawa, T.Hori, M.Teranishi and Y.Itoh) presented following results : 1) chromosome walking on the chicken Z and W chromosomes by screening clones from the BAC library of the female chicken genomic DNA,starting with genomic clones located near the premeiotic pairing ends of each chromosome, search for genes by the exon-trapping procedure, and location of clones by fluorescence in situ hybridization (FISH) on the lampbrush Z-W bivalent from a chicken oocyte, 2) male hypermethylated (MHM) region found at the middle of the short arm of the chicken Z chromosome and female … More specific transcription of this region into heterogeneous, high molecular weight RANA localized in nuclei, 3) determination of the gender of Oriental white stork by PCR using primers from the sex chromosome-specific sequences which are related to the EE0.6 sequence on the chicken W chromosome, and 4) a common origin of Carinatae and Ratitae sex chromosome pairs as demonstrated by FISH with three genomic clones ; EE0.6 from W chromosome, ZOV3 and IREBP from Z chromosome of chickens.I.Solovei presented the results of joint experiments with A.Ogawa and S.Mizuno that Xhol- and EcoRI-family repetitive sequences on the chicken W chromosome forms individually specific chromomeres on the premeiotic lampbruch W chromosome and that chromomere sizes vary extensively in accordance with changes of their repetition frequencies. S.Mizuno and co-investigators visited Roslin Institute at Edinburgh before the Symposium to talk with David Burt on the chicken gene mapping project. They conducted joint experiments with I.Solovei at the laboratry of H.Macgregor, after the Symposium, and could demonstrate that the MHM region was located and transcribed in a particular pair of loops on the lampbrush W chromosome of chickens. Less