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1.
《Molecular cell》2020,77(4):748-760.e9
2.
Adrián Melo-Carrillo Jacob C. Dunn Liliana Cortés-Ortiz 《American journal of primatology》2020,82(8):e23160
Genetic diversity provides populations with the possibility to persist in ever-changing environments, where selective regimes change over time. Therefore, the long-term survival of a population may be affected by its level of genetic diversity. The Mexican howler monkey (Alouatta palliata mexicana) is a critically endangered primate restricted to southeast Mexico. Here, we evaluate the genetic diversity and population structure of this subspecies based on 83 individuals from 31 groups sampled across the distribution range of the subspecies, using 29 microsatellite loci. Our results revealed extremely low genetic diversity (HO = 0.21, HE = 0.29) compared to studies of other A. palliata populations and to other Alouatta species. Principal component analysis, a Bayesian clustering method, and analyses of molecular variance did not detect strong signatures of genetic differentiation among geographic populations of this subspecies. Although we detect small but significant FST values between populations, they can be explained by a pattern of isolation by distance. These results and the presence of unique alleles in different populations highlight the importance of implementing conservation efforts in multiple populations across the distribution range of A. p. mexicana to preserve its already low genetic diversity. This is especially important given current levels of population isolation due to the extreme habitat fragmentation across the distribution range of this primate. 相似文献
3.
Kuang-Kai Liu Wei-Ru Qiu Emmanuel Naveen Raj Huei-Fang Liu Hou-Syun Huang Yu-Wei Lin 《Autophagy》2017,13(1):187-200
Selective macroautophagy/autophagy plays a pivotal role in the processing of foreign pathogens and cellular components to maintain homeostasis in human cells. To date, numerous studies have demonstrated the uptake of nanoparticles by cells, but their intracellular processing through selective autophagy remains unclear. Here we show that carbon-based nanodiamonds (NDs) coated with ubiquitin (Ub) bind to autophagy receptors (SQSTM1 [sequestosome 1], OPTN [optineurin], and CALCOCO2/NDP52 [calcium binding and coiled-coil domain 2]) and are then linked to MAP1LC3/LC3 (microtubule-associated protein 1 light chain 3) for entry into the selective autophagy pathway. NDs are ultimately delivered to lysosomes. Ectopically expressed SQSTM1-green fluorescence protein (GFP) could bind to the Ub-coated NDs. By contrast, the Ub-associated domain mutant of SQSTM1 (ΔUBA)-GFP did not bind to the Ub-coated NDs. Chloroquine, an autophagy inhibitor, prevented the ND-containing autophagosomes from fusing with lysosomes. Furthermore, autophagy receptors OPTN and CALCOCO2/NDP52, involved in the processing of bacteria, were found to be involved in the selective autophagy of NDs. However, ND particles located in the lysosomes of cells did not induce mitotic blockage, senescence, or cell death. Single ND clusters in the lysosomes of cells were observed in the xenografted human lung tumors of nude mice. This study demonstrated for the first time that Ub-coated nanoparticles bind to autophagy receptors for entry into the selective autophagy pathway, facilitating their delivery to lysosomes. 相似文献
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6.
《Bioorganic & medicinal chemistry letters》2014,24(11):2571-2577
We report the discovery of highly potent and selective non-steroidal glucocorticoid receptor modulators with PK properties suitable for inhalation. A high throughput screen of the AstraZeneca compound collection identified sulfonamide 3 as a potent non-steroidal glucocorticoid receptor ligand. Further optimization of this lead generated indazoles 30 and 48 that were progressed to characterization in in vivo models. X-ray crystallography was used to gain further insight into the binding mode of selected ligands. 相似文献
7.
N. N. Starkova E. P. Koroleva T. V. Rotanova 《Russian Journal of Bioorganic Chemistry》2000,26(2):71-84
Selective proteolysis is one of the mechanisms for the maintenance of cell homeostasis via rapid degradation of defective
polypeptides and certain short-lived regulatory proteins. In prokaryotic cells, high-molecular-mass oligomeric ATP-dependent
proteases are responsible for selective protein degradation. In eukaryotes, most polypeptides are attacked by the multicatalytic
26S proteasome, and the degradation of the majority of substrates involves their preliminary modification with the protein
ubiquitin. The proteins undergoing the selective proteolysis often contain specific degradation signals necessary for their
recognition by the corresponding proteases.
This article is dedicated to the 25th Anniversary of the journal Bioorganicheskaya Khimiya 相似文献
8.
Christian Alvarez Glaucia Gon?alves Barbosa Raquel de Vasconcellos Carvalhaes de Oliveira Bernardina Penarrieta Morales Bodo Wanke Márcia dos Santos Lazéra 《Memórias do Instituto Oswaldo Cruz》2013,108(1):126-129
In this study, we evaluated several techniques for the detection of the yeast form of Cryptococcus in decaying wood and measured the viability of these fungi in environmental samples stored in the laboratory. Samples were collected from a tree known to be positive for Cryptococcus and were each inoculated on 10 Niger seed agar (NSA) plates. The conventional technique (CT) yielded a greater number of positive samples and indicated a higher fungal density [in colony forming units per gram of wood (CFU.g-1) ] compared to the humid swab technique (ST). However, the difference in positive and false negative results between the CT-ST was not significant. The threshold of detection for the CT was 0.05.103 CFU.g-1, while the threshold for the ST was greater than 0.1.103 CFU-1. No colonies were recovered using the dry swab technique. We also determined the viability of Cryptococcus in wood samples stored for 45 days at 25ºC using the CT and ST and found that samples not only continued to yield a positive response, but also exhibited an increase in CFU.g-1, suggesting that Cryptococcus is able to grow in stored environmental samples. The ST.1, in which samples collected with swabs were immediately plated on NSA medium, was more efficient and less laborious than either the CT or ST and required approximately 10 min to perform; however, additional studies are needed to validate this technique. 相似文献
9.
E. Kobyliansky S. Micle I. Hershkovitz B. Arensburg 《International Journal of Anthropology》1986,1(1):59-73
The dermatoglyphics of the Muzeina and Gebeliya Bedouin tribes, two small biologically isolated populations, leading a similar
nomadic life under the specific conditions of the Sinai desert, were studied. The differences found between the studied samples
concern particularly the frequencies of palmar and finger pattern types. These differences are in agreement with data on the
origin of the tribes, a Negro and/or European admixture being evident in the Gebeliya dermatoglyphics. The coefficients of
variation for some quantitative dermatoglyphic traits, presumably with a polygenic determination, are lower in the Muzeina
than in the Gebeliya sample. Isolation and consanguinity may exert their influence on the dermatoglyphic traits influencing
the frequencies of the corresponding genes. 相似文献
10.
Neopomacentrus filamentosus, a common damselfish on the Indo–Australian archipelago, undergoes significant shifts in size and mitochondrial genetic structure upon larval settlement and metamorphosis to juvenile stages. We characterized five polymorphic microsatellite loci in order to study temporal genetic shifts within a single generation of N. filamentosus sampled first as larval settlers then again as demersal juvenile recruits. All loci were extremely polymorphic and exhibited high levels of heterozygosity. While all loci from the larval samples conformed to Hardy – Weinberg expectations, significant heterozygote deficiencies were seen in two loci in the juvenile samples, likely due to extreme size‐selective mortality imposed post‐settlement. 相似文献