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11.
Ken-ichi Takita Akira Tanigami Takashi Tokino Carol Jones Yusuke Nakamura 《Genomics》1992,13(4):1296-1299
Fifty-four clones containing human inserts were selected from a cosmid library constructed from a somatic cell hybrid containing chromosome 11p15.3-p15.5 as its only human complement. In 32 of these clones, 63 polymorphic systems were identified with a panel of restriction enzymes: 57 conventional RFLP systems and 6 highly polymorphic VNTR systems. Although we examined the cosmid with only seven enzymes, 18 clones (including 6 VNTRs) were polymorphic with three or more enzymes. The results suggested that DNA sequences on the peritelomeric region of chromosome 11p tend to be highly variable. Because these markers are highly informative, they will be excellent resources for investigations of hereditary diseases and tumor suppressor genes in this region of chromosome 11. 相似文献
12.
Kanji Ishizaki Asao Noda Mituo Ikenaga Kenji Ida Keiichi Omoto Yusuke Nakamura Ken-ichi Matsubara 《Human genetics》1985,71(3):261-262
Summary The plasmid clone which contains human salivary amylase cDNA was used to detect restriction fragment length polymorphisms
(RFLPs). After double digestion with Pst 1 and Bam H1, a polymorphism with two alleles was observed. In Japanese, frequencies of these alleles, tentatively called 5.7kb and 6.5kb
fragment alleles, are 0.55 and 0.45, respectively. 相似文献
13.
The ascidian egg contains muscle and endoderm determinants that play critical roles in the specification of muscle and endoderm cells, respectively. Endoderm cells of the ascidian embryo express alkaline phosphatase (AP) as a tissue-specific enzyme. We obtained egg fragments from the unfertilized eggs of Ciona savignyi by means of centrifugal force. The largest fragment (red fragments) contained the egg nucleus while other small fragments (black, clear and brown fragments) were anucleate. When inseminated, only red fragments developed into partial embryos, which showed only epidermis cell differentiation and, very rarely, AP activity. When red fragments were fused with other fragments, only black fragments promoted AP expression, suggesting that endoderm determinants were concentrated in the black fragments. A lower dose (1500 J/m2 ) of ultraviolet (UV) light did not eliminate the AP-promoting ability of black fragments, while this dose significantly repressed the ability to promote the expression of the muscle-marker. A higher dose (4500 J/m2 ) of UV light markedly reduced the AP-promoting activity of black fragments. These results suggest that factors for endodermal AP development are inactivated by UV irradiation, but are more resistant than muscle determinants. 相似文献
14.
cDNA cloning and tissue-specific expression of a novel basic helix-loop-helix/PAS factor (Arnt2) with close sequence similarity to the aryl hydrocarbon receptor nuclear translocator (Arnt). 总被引:11,自引:1,他引:10 下载免费PDF全文
15.
Takeshi K. Watanabe Toyomasa Katagiri Mikio Suzuki Fumio Shimizu Tsutomu Fujiwara Naohide Kanemoto Yusuke Nakamura Yoshikatsu Hirai Hiroumi Maekawa Ei-ichi Takahashi 《Genomics》1996,38(3):273
From a human fetal-brain cDNA library we isolated two novel genes encoding peptides containing six EGF-like repeats. Both showed significant homologies with nel, a gene strongly expressed in neural tissues of chicken. The cDNAs, designated NELL1 (nel-like, type 1) and NELL2 (nel-like, type 2), contained open reading frames encoding 810 and 816 amino acids, respectively. NELL2 is strongly expressed in brain of adult and fetus but only weakly in fetal kidney. NELL1 and NELL2 were mapped by FISH to chromosomal bands 11p15.1–p15.2 and 12q13.11–q13.12, respectively. 相似文献
16.
The human S1-5 gene (fibrillin-like; FBNL) was originally isolated from a subtractively enriched cDNA library established from a subject with Werner syndrome (WS). We isolated genomic clones containing the entire S1-5 gene and determined its genomic structure including the exon–intron organization. The gene spanned approximately 18 kb of genomic DNA and consisted of 12 exons. Its expression was abundant in all tissues examined except brain and peripheral leukocytes, where it was undetectable. In addition, we have mapped S1-5 by fluorescencein situhybridization to chromosome 2p16, a position that excludes it as a candidate for WS. Our data should facilitate an understanding of the function and regulation of S1-5 in human tissues. 相似文献
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Presymptomatic direct detection of adenomatous polyposis coli (APC) gene mutations in familial adenomatous polyposis 总被引:5,自引:0,他引:5
The recent identification of the familial adenomatous polyposis (FAP) gene (designated as APC) enables conclusive genetic testing of at-risk family members for the specific mutation in families in which the germline gene mutation has been characterized. Presymptomatic molecular diagnosis of FAP was performed by direct direction of mutations in lymphocyte DNA in four families. Each of the families has a different mutation of the APC gene. Twenty-seven offspring of affected individuals (a priori risk of 50%) were tested. Ten of the 27 had already developed clinical features of FAP. Of the remaining seventeen, two had had a negative colon exam at an early age, and nine had never had colon exams (mean age, 12.1±3.1 SD years). Six children from this group (54%) were found to carry their affected parent's mutation. No change in the conventional FAP colon screening regimen is recommended for these children. In contrast, when direct tests indicate that an individual does not have the FAP mutation, we recommended that screening be decreased. Reduction of uncertainty for at-risk FAP family members is an important benefit of genetic testing. 相似文献
20.
Naoyuki Nakahama Ryosuke Okano Yuichiro Nishimoto Yusuke Nakatani Asato Noishiki Naoki Ogawa 《Entomological Science》2023,26(2):e12545
Wetland biodiversity is currently declining on a global scale. Wetland biodiversity understanding is critical for determining the wetlands' conservation value. In this study, Macroplea Samouelle, 1819 (Coleoptera: Chrysomelidae) was discovered in Aomori Prefecture, Honshu Island, Japan. Only two Macroplea species have been recorded in Japan, M. japana (Jacoby, 1885) and M. mutica (Fabricius, 1792). Macroplea japana had been unrecorded for 60 years before being rediscovered in Honshu Island in 2022, and a single adult M. mutica female was discovered in Hokkaido Prefecture in 2003. The discovered individuals were concluded to be M. mutica based on morphological and molecular analyses. Although morphological differences were observed with the Eurasian M. mutica individuals, the male genitalia was nearly identical to M. mutica. For the molecular phylogenetic analysis based on COI and 28S sequences, Macroplea individuals in Japan were clustered with M. mutica on the Eurasian Continent. This is the first record of this species on Honshu Island (and the second in Japan), as well as the first record of adult males. This species would require conservation policies and additional distributional surveys. 相似文献