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81.
The guinea pig intestinal symbiont Metabacterium polyspora is an uncultured, endospore-forming member of the Firmicutes. Unlike most endospore-forming bacteria, sporulation is an obligate part of the M. polyspora life cycle when it is associated with a guinea pig. Binary fission is limited to a brief period in its life cycle, if exhibited at all. Instead, M. polyspora relies on the formation of multiple endospores for reproduction. Sporulation is initiated immediately after germination, which leaves little time for the cell to accumulate resources to support spore formation. Using immunolocalization of the nucleotide analogue bromodeoxyuridine (BrdU), we were able to follow replication dynamics in M. polyspora . BrdU was provided to cells within the guinea pig intestinal tract. BrdU was incorporated into DNA located within the forespores throughout development, at all stages prior to spore maturation. Our results suggest that in M. polyspora , DNA replication within the forespore is not suppressed during sporulation as it is in other endospore-forming bacteria. Replication within forespores would allow M. polyspora to maximize its reproductive potential and supply each endospore with at least one complete copy of the genome. 相似文献
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Azemi Nur Farah Hani Misnan Rosmilah Keong Bun Poh Mokhtar Marina Kamaruddin Nurhaida Fah Wong Chee Yadzir Zailatul Hani Mohamad Yadzir Hani Mohamad Bakhtiar Faizal Abdullah Noormalin Arip Masita Ateshan Haidr Msahir 《Molecular biology reports》2021,48(10):6709-6718
Molecular Biology Reports - Tropomyosin is a major allergen in crustaceans, including mud crab species, but its molecular and allergenic properties in Scylla olivacea are not well known. Thus, this... 相似文献
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Douglas A. Currie Rebekah Corlew Jan de Vente William J. Moody 《Developmental neurobiology》2009,69(4):255-266
The second messenger cyclic guanosine monophosphate (cGMP) plays many roles during nervous system development. Consequently, cGMP production shows complex patterns of regulation throughout early development. Elevated glutamate levels are known to increase cGMP levels in the mature nervous system. A number of clinical conditions including ischemia and perinatal asphyxia can result in elevated glutamate levels in the developing brain. To investigate the effects of elevated glutamate levels on cGMP in the developing cortex we exposed mouse brain slices to glutamate or N‐methyl D ‐aspartate (NMDA). We find that at early postnatal stages when the endogenous production of cGMP is high, glutamate or NMDA exposure results in a significant lowering of the overall production of cGMP in the cortex, unlike the situation in the mature brain. However, this response pattern is complex with regional and cell‐type specific exceptions to the overall lowered cGMP production. These data emphasize that the response of the developing brain to physiological disturbances can be different from that of the mature brain, and must be considered in the context of the developmental events occurring at the time of disturbance. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009 相似文献
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Rebekah Tillotson Justyna Cholewa-Waclaw Kashyap Chhatbar John C. Connelly Sophie A. Kirschner Shaun Webb Martha V. Koerner Jim Selfridge David A. Kelly Dina De Sousa Kyla Brown Matthew J. Lyst Skirmantas Kriaucionis Adrian Bird 《Molecular cell》2021,81(6):1260-1275.e12
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Rebekah van Bruggen Christian Gualtieri Alexandra Iliescu Chalisa Louicharoen Cheepsunthorn Punchalee Mungkalasut Jean-Fran?ois Trape David Modiano Bienvenu Sodiomon Sirima Pratap Singhasivanon Mark Lathrop Anavaj Sakuntabhai Jean-Fran?ois Bureau Philippe Gros 《PloS one》2015,10(12)
Pyruvate kinase (PKLR) is a critical erythrocyte enzyme that is required for glycolysis and production of ATP. We have shown that Pklr deficiency in mice reduces the severity (reduced parasitemia, increased survival) of blood stage malaria induced by infection with Plasmodium chabaudi AS. Likewise, studies in human erythrocytes infected ex vivo with P. falciparum show that presence of host PK-deficiency alleles reduces infection phenotypes. We have characterized the genetic diversity of the PKLR gene, including haplotype structure and presence of rare coding variants in two populations from malaria endemic areas of Thailand and Senegal. We investigated the effect of PKLR genotypes on rich longitudinal datasets including haematological and malaria-associated phenotypes. A coding and possibly damaging variant (R41Q) was identified in the Thai population with a minor allele frequency of ~4.7%. Arginine 41 (R41) is highly conserved in the pyruvate kinase family and its substitution to Glutamine (R41Q) affects protein stability. Heterozygosity for R41Q is shown to be associated with a significant reduction in the number of attacks with Plasmodium falciparum, while correlating with an increased number of Plasmodium vivax infections. These results strongly suggest that PKLR protein variants may affect the frequency, and the intensity of malaria episodes induced by different Plasmodium parasites in humans living in areas of endemic malaria. 相似文献
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Genetic connectivity of a coral reef ecosystem predator: the population genetic structure and evolutionary history of the Caribbean reef shark (Carcharhinus perezi)
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