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101.
102.
Jing Che Junfeng Pang Hui Zhao Guan-fu Wu Er-mi Zhao Ya-ping Zhang 《Biochemical Systematics and Ecology》2007
The phylogeny of representative species of Chinese ranids was reconstructed using two nuclear (tyrosinase and rhodopsin) and two mitochondrial (12S rRNA, 16S rRNA) DNA fragments. Maximum parsimony, Bayesian, and maximum likelihood analyses were employed. In comparison with the results from nuclear and mitochondrial data, we used nuclear gene data as our preferred phylogenetic hypothesis. We proposed two families (Ranidae, Dicroglossidae) for Chinese ranids, with the exception of genus Ingerana. Within Dicroglossidae, four tribes were supported including Dicroglossini, Paini, Limnonectini, and Occidozygini. A broader sampling strategy and evidence from additional molecular markers are required to decisively evaluate the evolutionary history of Chinese ranids. 相似文献
103.
The Bacillus subtilis genome contains two tandem genes, ebrA and ebrB, which encode two homologues of the SMR family of multidrug efflux transporters. The sequences of EbrA and EbrB are highly similar to each other and to that of EmrE, the prototypical SMR transporter of Escherichia coli. Drug resistance profiling and drug binding experiments showed that the presence of both EbrA and EbrB is required for proper transport function. EbrA and EbrB directly interact and combine to form a functional transporter. They likely form a heterodimer in analogy to the EmrE homodimer. Mutagenesis experiments indicate that the conserved membrane-embedded glutamates in the first transmembrane helices of both EbrA and EbrB are required for multidrug efflux activity. However, the two glutamates are nonequivalent since EbrA E15 is required for substrate binding while EbrB E14 is not. Our studies support a model in which functional residues in EbrAB are relegated to at least two sets that participate in distinct steps of the active drug transport process. 相似文献
104.
目的:研究吗啡对胎动、心率、孵化率、孵化时间、雏鸡体重等的影响。方法:以气室给药的方式给鸡胚注射吗啡,记录胎动、心率、孵化率、孵化时间、雏鸡体重。结果:吗啡可以缩短雏鸡的孵化时间,降低雏鸡的孵化率,并导致雏鸡出现运动障碍;20mg/kg吗啡剂量和12—16胚龄的给药时间,鸡胚孵化率最高,残疾率最低;吗啡导致胚胎心率加快,胎动减少(P〈0.05)。结论:吗啡对胚胎发育有损伤作用,损伤程度与吗啡剂量和给药时间有关。 相似文献
105.
Takai R Kaneda T Isogai A Takayama S Che FS 《Bioscience, biotechnology, and biochemistry》2007,71(2):590-593
We established a new plant defense response assay using a transient expression system in rice protoplasts. The assay system sensitively detected defense induction by flagellin, which had previously been assigned to a specific elicitor. Our assay system provides a rapid and efficient way to dissect rice defense mechanisms. 相似文献
106.
Che FY Zhang X Berezniuk I Callaway M Lim J Fricker LD 《Journal of proteome research》2007,6(12):4667-4676
Sample preparation for neuropeptidomic studies is a critical issue since protein degradation can produce high levels of peptides that obscure the endogenous neuropeptides. We compared different extraction conditions for the recovery of neuropeptides and the formation of protein breakdown fragments from mouse hypothalami. Sonication and heating in water (70 degrees C for 20 min) followed by cold acid and centrifugation enabled the efficient extraction of many neuropeptides without the formation of protein degradation fragments seen with hot acid extractions. The hot water/cold acid extraction procedure resulted in the reproducible recovery of many hypothalamic peptides, including several novel peptides. 相似文献
107.
Wang Linwen Wang Hui Wang Yuncai Che Yue Ge Zhiwei Mao Lingfeng 《Biodiversity and Conservation》2022,31(7):1771-1796
Biodiversity and Conservation - As a form of green infrastructure, green roofs can enhance urban biodiversity by providing complex vegetation structures, supplying increased foraging and roosting... 相似文献
108.
109.
Markus Schueler Daniela?A. Braun Gayathri Chandrasekar Heon?Yung Gee Timothy?D. Klasson Jan Halbritter Andrea Bieder Jonathan?D. Porath Rannar Airik Weibin Zhou Joseph?J. LoTurco Alicia Che Edgar?A. Otto Detlef B?ckenhauer Neil?J. Sebire Tomas Honzik Peter?C. Harris Sarah?J. Koon Meral Gunay-Aygun Sophie Saunier Klaus Zerres Nadina?Ortiz Bruechle Joost?P.H. Drenth Laurence Pelletier Isabel Tapia-Páez Richard?P. Lifton Rachel?H. Giles Juha Kere Friedhelm Hildebrandt 《American journal of human genetics》2015,96(1):81-92
Nephronophthisis-related ciliopathies (NPHP-RC) are recessive diseases characterized by renal dysplasia or degeneration. We here identify mutations of DCDC2 as causing a renal-hepatic ciliopathy. DCDC2 localizes to the ciliary axoneme and to mitotic spindle fibers in a cell-cycle-dependent manner. Knockdown of Dcdc2 in IMCD3 cells disrupts ciliogenesis, which is rescued by wild-type (WT) human DCDC2, but not by constructs that reflect human mutations. We show that DCDC2 interacts with DVL and DCDC2 overexpression inhibits β-catenin-dependent Wnt signaling in an effect additive to Wnt inhibitors. Mutations detected in human NPHP-RC lack these effects. A Wnt inhibitor likewise restores ciliogenesis in 3D IMCD3 cultures, emphasizing the importance of Wnt signaling for renal tubulogenesis. Knockdown of dcdc2 in zebrafish recapitulates NPHP-RC phenotypes, including renal cysts and hydrocephalus, which is rescued by a Wnt inhibitor and by WT, but not by mutant, DCDC2. We thus demonstrate a central role of Wnt signaling in the pathogenesis of NPHP-RC, suggesting an avenue for potential treatment of NPHP-RC. 相似文献
110.
Shengjian Li Yu-He Liang Jennifer Mariano Meredith B. Metzger Daniel K. Stringer Ventzislava A. Hristova Jess Li Paul A. Randazzo Yien Che Tsai Xinhua Ji Allan M. Weissman 《The Journal of biological chemistry》2015,290(51):30225-30239
RING proteins constitute the largest class of E3 ubiquitin ligases. Unlike most RINGs, AO7 (RNF25) binds the E2 ubiquitin-conjugating enzyme, UbcH5B (UBE2D2), with strikingly high affinity. We have defined, by co-crystallization, the distinctive means by which AO7 binds UbcH5B. AO7 contains a structurally unique UbcH5B binding region (U5BR) that is connected by an 11-amino acid linker to its RING domain, forming a clamp surrounding the E2. The U5BR interacts extensively with a region of UbcH5B that is distinct from both the active site and the RING-interacting region, referred to as the backside of the E2. An apparent paradox is that the high-affinity binding of the AO7 clamp to UbcH5B, which is dependent on the U5BR, decreases the rate of ubiquitination. We establish that this is a consequence of blocking the stimulatory, non-covalent, binding of ubiquitin to the backside of UbcH5B. Interestingly, when non-covalent backside ubiquitin binding cannot occur, the AO7 clamp now enhances the rate of ubiquitination. The high-affinity binding of the AO7 clamp to UbcH5B has also allowed for the co-crystallization of previously described and functionally important RING mutants at the RING-E2 interface. We show that mutations having marked effects on function only minimally affect the intermolecular interactions between the AO7 RING and UbcH5B, establishing a high degree of complexity in activation through the RING-E2 interface. 相似文献