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91.
Cell morphogenesis is a complex process that relies on a diverse array of proteins and pathways. We have identified a transglutaminase-like protein (Cyk3p) that functions in fission yeast morphogenesis. The phenotype of a cyk3 knockout strain indicates a primary role for Cyk3p in cytokinesis. Correspondingly, Cyk3p localizes both to the actomyosin contractile ring and the division septum, promoting ring constriction, septation, and subsequent cell separation following ring disassembly. In addition, Cyk3p localizes to polarized growth sites and plays a role in cell shape determination, and it also appears to contribute to cell integrity during stationary phase, given its accumulation as dynamic puncta at the cortex of such cells. Our results and the conservation of Cyk3p across fungi point to a role in cell wall synthesis and remodeling. Cyk3p possesses a transglutaminase domain that is essential for function, even though it lacks the catalytic active site. In a wider sense, our work illustrates the physiological importance of inactive members of the transglutaminase family, which are found throughout eukaryotes. We suggest that the proposed evolution of animal transglutaminase cross-linking activity from ancestral bacterial thiol proteases was accompanied by the emergence of a subclass whose function does not depend on enzymatic activity. 相似文献
92.
93.
Anti-hypertensive activity of genetically modified soybean seeds accumulating novokinin 总被引:1,自引:0,他引:1
Yamada Y Nishizawa K Yokoo M Zhao H Onishi K Teraishi M Utsumi S Ishimoto M Yoshikawa M 《Peptides》2008,29(3):331-337
Novokinin (Arg-Pro-Leu-Lys-Pro-Trp), which has been designed based on the structure of ovokinin (2-7), significantly reduces the systolic blood pressure at a dose of 100 microg/kg after oral administration in spontaneously hypertensive rats (SHRs). In this study, we generated a transgenic soybean which accumulates novokinin. A vector encoding a modified beta-conglycinin alpha' subunit (4novokinin-alpha') in which four novokinin sequences have been incorporated by site-directed mutagenesis was introduced into somatic embryos by whisker-mediated gene transformation to produce a transgenic soybean. The 4novokinin-alpha' occupied 0.5% of total soluble protein and 5% of the beta-conglycinin alpha' subunit in the transgenic soybean seeds. Protein extracted from the transgenic soybean reduced systolic blood pressure after single oral administration in SHRs at a dose of 0.15 g/kg. Defatted flour from the transgenic soybean also reduced the systolic blood pressure at a dose of 0.25 g/kg. Thus, the 4novokinin-alpha' produced in soybean exhibited an anti-hypertensive activity in SHRs after oral administration. 相似文献
94.
Nomura T Ueyama T Ashihara E Tateishi K Asada S Nakajima N Isodono K Takahashi T Matsubara H Oh H 《Biochemical and biophysical research communications》2008,365(4):863-869
The existence of skeletal muscle-derived stem cells (MDSCs) has been suggested in mammals; however, the signaling pathways controlling MDSC proliferation remain largely unknown. Here we report the isolation of myosphere-derived progenitor cells (MDPCs) that can give rise to beating cardiomyocytes from adult skeletal muscle. We identified that follistatin, an antagonist of TGF-β family members, was predominantly expressed in MDPCs, whereas myostatin was mainly expressed in myogenic cells and mature skeletal muscle. Although follistatin enhanced the replicative growth of MDPCs through Smad2/3 inactivation and cell cycle progression, disruption of myostatin did not increase the MDPC proliferation. By contrast, inhibition of activin A (ActA) or growth differentiation factor 11 (GDF11) signaling dramatically increased MDPC proliferation via down-regulation of p21 and increases in the levels of cdk2/4 and cyclin D1. Thus, follistatin may be an effective progenitor-enhancing agent neutralizing ActA and GDF11 signaling to regulate the growth of MDPCs in skeletal muscle. 相似文献
95.
Arthur Bob Karnuah Hirohide Uenishi Sachiko Kiuchi Misaki Kojima Akira Onishi Hiroshi Yasue Tadayoshi Mitsuhashi 《Mammalian genome》2001,12(7):518-523
A swine resource family was constructed at the National Institute of Animal Industry, Japan, in order to determine the genetic
regions responsible for economically important traits, including fetus development. To identify genes expressed in the early
stage of embryo development, we cataloged and mapped genes expressed in a 28-day-old normal pig embryo. In this effort, we
have mapped 64 genes, which have map information in human genome onto a swine radiation hybrid (RH) map, IMpRH. These mappings
provided additional chromosomal homologies between swine and human to improve the comparative map between the two species.
The distribution of the genes assigned to swine chromosomes are as follows: 9 genes were assigned on SSC6; 6 genes each assigned
on SSC5 and SSC14; 5 genes each assigned on SSC3, SSC4, and SSC8; 4 genes each assigned on SSC1, SSC7, SSC9, and SSC15; 3
genes each assigned on SSC2, SSC13 and SSCX; and 1 gene each assigned on SSC10, SSC11, and SSC16. Moreover, the present findings
revealed 18 new chromosomal homologies between pig and human. Briefly, SSC3 regions were indicated to correspond with HSA1
and HSA10; SSC4 with HSA6; SSC5 with HSA2, HSA15, and HSA16; SSC6 with HSA3, HSA6, and HSA20; SSC7 with HSA11; SSC8 with HSA3,
HSA6, and HSA7; SSC9 with HSA8; SSC13 with HSA1; SSC14 with HSA13; SSC15 with HSA19; SSC16 with HSA9.
Received: 19 December 2000 / Accepted: 13 March 2001 相似文献
96.
Inosine triphosphate (ITP) does not serve as a substrate for myosin light-chain kinase from gizzard muscle. That is to say, myosin light-chain is not phosphorylated in ITP media. Nevertheless, at pH 6.8, 1 mM or 5 mM ITP induces superprecipitation of skeletal acto-gizzard myosin. The ITP-induced superprecipitation occurs in the absence or presence of calcium ions, and regardless of whether gizzard myosin is phosphorylated or not. On the other hand, at pH 8, 5 MM ITP induces practically no superprecipitation of skeletal acto-gizzard unphosphorylated myosin, whereas it does induce a strong superprecipitation of skeletal acto-gizzard phosphorylated myosin. Superprecipitation is also independent of the presence or absence of calcium ions. 相似文献
97.
Koya Yamashiro Daisuke Sato Hideaki Onishi Kazuhiro Sugawara Sho Nakazawa Hirofumi Shimojo Kosuke Akatsuka Hiroki Nakata Atsuo Maruyama 《PloS one》2015,10(11)
Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4) in 12 baseball players (baseball group) and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group). The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs) were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT). Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes. 相似文献
98.
T Onishi 《Biochemical and biophysical research communications》1970,41(2):344-352
99.