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181.
In mice, the conditional knockout strategy using the Cre-loxP system is useful for various types of research. The Cre mouse line with progesterone receptor promoter (PgrCre) has been widely used to produce specific uterine gene-deficient mice, but in the Cre line, endogenous Pgr gene is replaced by Cre recombinase gene, which makes the breeding of homozygous mice (PgrCre/Cre) difficult because they are infertile. Yang et al. (2013, https://10.1016/j.cell.2013.04.017 ) reported the generation of another PgriresCre mouse line that still has endogenous Pgr gene, and they inserted Cre recombinase downstream of the Pgr gene via an internal ribosome entry site (IRES). It is possible that this new PgriresCre line would be useful for uterine research as the mice can be bred as homozygotes (PgriresCre/iresCre). Herein, we confirmed the PgriresCre mice effectively directed recombination in the female reproductive tract and was capable of genetic alteration in the endometrium that enables the studies of its uterine function. Our findings demonstrate that the new PgriresCre mouse line is also useful for the generation of uterine-specific knockout mice. The findings using PgriresCre mouse will contribute to the understanding of reproductive systems and diseases in humans and domestic animals.  相似文献   
182.
183.
Dwarf plants were obtained in an F2 population of a cross betweenSolanum chacoense (clone chc 525-3) andS. phureja (clone 1.22). Segregation analyses in F2 and backcross populations suggested that the dwarfism was controlled by a single recessive gene transmitted fromS. phureja clone 1.22. The dwarf plants responded to treatment with gibberellic acid, which recovered normal growth. We named this gene‘ga 2’. Linkage analysis of the genega 2 with RFLP and RAPD markers indicated that the genega 2 was located on the most or near distal end of chromosome 7.  相似文献   
184.
Repetitive DNA sequences, ManDra and ManBgl, were isolated from the DraI and BglII digests of the genomic DNA of Misgurnus anguillicaudatus, respectively. A primer set of ManDra distinguished two genetically different groups (A and B) of M. anguillicaudatus by specific electrophoretograms. A primer set of ManBgl amplified the DNA of M. anguillicaudatus and M. mizolepis. The individuals of M. anguillicaudatus were divided into two groups depending on the fragment sizes, in which the groups A and B (B-1 and B-2) showed 400 and 460 bp, respectively. M. mizolepis was distinguished by a different pattern (400-, 460-, and 510-bp fragments). PCR–RFLP analyses of recombination activating gene 1 gave a clear difference between A or B-2 (443-bp fragment) and B-1 groups (296- and 147-bp fragments). Clonal lineages and hybrids between B-1 and B-2 groups could be identified by appearance of three fragments (443, 296, and 147 bp). The combined analyses using the above three nuclear markers discriminated among nuclear genomes of genetic groups (A, B-1 and B-2) of M. anguillicaudatus and M. mizolepis. In several localities, natural hybridizations between the group B-1 and B-2 loaches and introgressions of clonal mitochondrial genomes into the group B-1 loaches were detected.  相似文献   
185.
We investigated the source of spontaneous polyploidization in the critically endangered Acipenser mikadoi. Fourteen sib progeny of A. mikadoi and 11 hybrids between an A. mikadoi female and a Huso dauricus male, all showing atypically high ploidy, were analysed. Parent assignment based on five highly polymorphic microsatellite markers confirmed spontaneous duplication of maternal chromosome sets via retention of the second polar body to be the source of spontaneous polyploidization. To our knowledge, this provides the first evidence of the maternal origin of spontaneous polyploidization in A. mikadoi. Factorial correspondence analysis of the multilocus microsatellite genotypes placed the parent fish of spontaneous polyploids in clearly delineated clusters of A. mikadoi and H. dauricus, and parent fish had mitochondrial control region haplotypes corresponding to their presumed species. Thus, parent fish were confirmed to be of pure genetic origin, and hybridization did not promote the observed spontaneous polyploidization.  相似文献   
186.
Antimicrobial peptides (AMPs) are found widespread in nature and possess antimicrobial and immunomodulatory activities. Due to their multifunctional properties, these peptides are a focus of growing body of interest and have been characterized in several fish species. Due to their similarities in amino-acid composition and amphipathic design, it has been suggested that neuropeptides may be directly involved in the innate immune response against pathogen intruders. In this review, we report the molecular characterization of the fish-specific AMP piscidin1, the production of an antibody raised against this peptide and the immunohistochemical identification of this peptide and enkephalins in the neuroepithelial cells (NECs) in the gill of several teleost fish species living in different habitats. In spite of the abundant literature on Piscidin1, the biological role of this peptide in fish visceral organs remains poorly explored, as well as the role of the neuropeptides in neuroimmune interaction in fish. The NECs, by their role as sensors of hypoxia changes in the external environments, in combination with their endocrine nature and secretion of immunomodulatory substances would influence various types of immune cells that contain piscidin, such as mast cells and eosinophils, both showing interaction with the nervous system. The discovery of piscidins in the gill and skin, their diversity and their role in the regulation of immune response will lead to better selection of these immunomodulatory molecules as drug targets to retain antimicrobial barrier function and for aquaculture therapy in the future.  相似文献   
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