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41.
It was found that human recombinant interferon-alpha (Hu rIFN-alpha) was biologically active in the guinea pig. Namely, intratumor injection of either Hu rIFN-alpha A or A/D regressed tumors and prevented metastasis of guinea-pig line 10 tumor. These rIFNs augmented splenic natural killer activity of the guinea pig and reduced the cytopathic effect of virus on guinea-pig cells. Hu IFN-gamma showed no such activity. 相似文献
42.
43.
Arakawa Tsutomu Tokunaga Masao Kita Yoshiko Niikura Takako Baker Richard W. Reimer Janice M. Leschziner Andres E. 《The protein journal》2021,40(6):867-875
The Protein Journal - Difference circular dichroism (CD) spectroscopy was used here to characterize changes in structure of flexible peptides upon altering their environments. Environmental changes... 相似文献
44.
Matsujiro Ishibashi Tomoe Hayashi Chiho Yoshida Masao Tokunaga 《Extremophiles : life under extreme conditions》2013,17(4):585-591
Nucleoside diphosphate kinase (HsNDK) from an extremely halophilic archaea, Halobacterium salinarum, is composed of a homo hexamer, assembled as a trimer of basic dimeric units. It requires >2 M NaCl for refolding, although it does not require NaCl for stability or enzymatic activity below 30 °C. A HisN111L mutant with an N-terminal extension sequence containing hexa-His tag, in which Asn111 was replaced with Leu, was designed to be less stable between basic dimeric units. This mutant can lose between 6 and 12 hydrogen bonds between basic dimeric units in the hexamer structure. The HisN111L mutant had enhanced salt requirements for enzymatic activity and refolding even though the secondary structure of the HisN111L mutant was confirmed to be similar to the control, HisNDK, in low and high salt solutions using circular dichroism. We reported previously that G114R and D148C mutants, which had enhanced interactions between basic dimeric units, showed facilitated refolding and stabilization in low salt solution. The results of this study help to elucidate the process for engineering industrial enzymes by controlling subunit–subunit interactions through mutations. 相似文献
45.
Tanida Kotomi Shimada Mihoko Khor Seik-Soon Toyoda Hiromi Kato Kayoko Kotorii Nozomu Kotorii Tatayu Ariyoshi Yu Kato Takao Hiejima Hiroshi Ozone Motohiro Uchimura Naohisa Ikegami Azusa Kume Kazuhiko Kanbayashi Takashi Imanishi Aya Kamei Yuichi Hida Akiko Wada Yamato Kuroda Kenji Miyamoto Masayuki Hirata Koichi Takami Masanori Yamada Naoto Okawa Masako Omata Naoto Kondo Hideaki Kodama Tohru Inoue Yuichi Mishima Kazuo Honda Makoto Tokunaga Katsushi Miyagawa Taku 《Sleep and biological rhythms》2022,20(1):137-148
Sleep and Biological Rhythms - Idiopathic hypersomnia (IH) is a rare sleep disorder characterized by excessive daytime sleepiness, great difficulty upon awakening, and prolonged sleep time. In... 相似文献
46.
Makoto Bannai Katsushi Tokunaga Tadashi Imanishi Shinji Harihara Kiyoshi Fujisawa Takeo Juji Keiichi Omoto 《American journal of physical anthropology》1996,101(1):1-9
The Ainu people are considered to be the descendants of preagricultural native populations of northern Japan, while the majority of the population of contemporary Japan (Wajin) is descended mainly from postneolithic migrants. Polymorphisms of the HLA-DRB1, DRB3, and DQB1 alleles were investigated in DNA samples of 50 Ainu living in Hidaka district, Hokkaido. Unique features of the Ainu in this study were high incidences of DRB1*1401, DRB1*1406, and a newly described allele, DRB1*1106 (20%, 17%, and 5%, respectively). On the other hand, several common alleles in Wajin (DRB1*1502, 1302, 0803, and 1501) were found at relatively low frequencies (1–2%) in Ainu. Previously DRB1*1406 was described as a characteristic allele of some Native American or northeast Asian ethnic groups, and DRB1*1106 had been found in only two Singapore Chinese and one Korean. Principal component analysis of various populations based on HLA class II allele frequencies places the Ainu population midway between other east Asian populations, including Wajin, and Native Americans. These observations may support the hypothesis that the Ainu people are the descendants of some Upper Paleolithic populations of northeast Asia from which Native Americans are also descended. © 1996 Wiley-Liss, Inc. 相似文献
47.
Watanabe M Tsutsui K Hosoya O Tsutsui K Kumon H Tokunaga A 《Biochemical and biophysical research communications》2001,287(3):739-745
Amphiphysin I is a protein concentrated in nerve terminals and involved in the endocytosis of synaptic vesicle membrane. We show here that amphiphysin I is expressed in the rat testis, localized exclusively in the Sertoli cells. In the postnatal testicular development, expression of amphiphysin I was not evident at birth, but became significant at postnatal day 15 (P15), coinciding with the onset of spermatogenesis. The expression level of amphiphysin I increased 10-fold between P15 and P25 to reach the adult level. In adult testes reversibly damaged by ethane dimethane sulphonate administration, expression of amphiphysin I did not change following the damage, whereas the protein was transiently converted into its phosphorylated form. The increase in levels of phosphorylated amphiphysin I was closely associated with the severe histological damage to germ cells. The present findings suggest that amphiphysin I in Sertoli cells is involved in spermatogenesis, probably through endocytic processes. 相似文献
48.
Alpha4 protein as a common regulator of type 2A-related serine/threonine protein phosphatases 总被引:4,自引:0,他引:4
Nanahoshi M Tsujishita Y Tokunaga C Inui S Sakaguchi N Hara K Yonezawa K 《FEBS letters》1999,446(1):108-112
The catalytic activity of the C subunit of serine/threonine phosphatase 2A is regulated by the association with A (PR65) and B subunits. It has been reported that the alpha4 protein, a yeast homolog of the Tap42 protein, binds the C subunit of serine/threonine phosphatase 2A and protein phosphatase 2A-related protein phosphatases such as protein phosphatase 4 and protein phosphatase 6. In the present study, we showed that alpha4 binds these three phosphatases and the association of alpha4 reduces the activities of these phosphatases in vitro. In contrast, PR65 binds to the C subunit of serine/threonine phosphatase 2A but not to protein phosphatase 4 and protein phosphatase 6. These results suggest that the alpha4 protein is a common regulator of the C subunit of serine/threonine phosphatase 2A and protein phosphatase 2A-related protein phosphatases. 相似文献
49.
Kotliarova SE Toda T Takenaka O Matsushita I Hida A Shinka T Goto J Tokunaga K Nakagome Y Nakahori Y 《Human biology; an international record of research》1999,71(2):261-275
The origin of modern humans can be traced by comparing polymorphic sites in either mitochondria or genomic sequences between humans and other primates. The human Y chromosome has both a non-recombining region and X-Y homologous pseudo-autosomal regions. In the nonrecombining region events during evolution can be directly detected. At least a part of homology between Xq21 and Yp11 is a result of rather recent translocations from the X chromosome to the Y chromosome. DNA markers residing in the nonrecombining region of the human Y chromosome are potentially useful in tracing male-specific gene flow in human evolution. However, the number of available markers in the region is limited. Here, we report a novel X-Y homologous (CA)n repeat locus in the nonrecombining region of the Y chromosome. This marker, DXYS241, has several interesting features. Y- and X-chromosome alleles are distinguishable because the Y-chromosome alleles are shorter than the X-chromosome alleles most of the time. We developed 2 primer sets for specific examination of Y- and X-chromosome alleles. The marker should be useful in establishing relationships between populations based on patrilineal gene flow. Sequences homologous to DXYS241 are also found on the X chromosome of primates. Four events during primate evolution that led to the modern human Y chromosome were identified. 相似文献
50.