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The rough-toothed dolphin genome provides new insights into the genetic mechanism of its rough teeth
The rough-toothed dolphin (Steno bredanensis) is characterized by having teeth covered in finely wrinkled vertical ridges, which is a general manifestation of amelogenesis imperfecta. The rough surfaces are hypothesized to be an evolutionary morphological trait of feeding adaptation to increase the dolphin's grip on prey. Here, we assembled a rough-toothed dolphin genome and performed the comparative genomic analysis to reveal the genetic basis of the special enamel. Results showed that genes related to enamel development or dental diseases have undergone diversified adaptive changes that may shape the special enamel morphology of this dolphin species, including positive selection (CLDN19, PRKCE, SSUH2, and WDR72), rapid evolution (LAMB3), or unique amino acid substitutions (AMTN, ENAM, MMP20, and KLK4). Meanwhile, the historical demography of rough-toothed dolphin indicated several distinct population fluctuations associated with climate change. The genome-wide heterozygosity of this dolphin is in the middle of all published data for cetaceans. Although the population is considerable, there may be population or subspecies differentiation, and with the global warming and the increasing disturbance of human activities, we should pay more attention to protection in the future. Together, our study brings new insights into the genetic mechanisms that may have driven the evolution of the special enamel morphology in rough-toothed dolphins and provides the first results of genetic heterozygosity and population historical dynamics of this species, which have important guiding implications for the conservation of this dolphin species. 相似文献
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功能型酸奶独特的风味及保健功能,受到越来越多消费群体的青睐,有较好的消费市场和发展前景,也有较大的研究价值。本文在国内外研究基础上,对功能型酸奶常见的两种分类方式(按添加成分和消费者群体分类)、不同的保健功能(解酒、抗氧化、通便、清热解毒和对砷毒性的缓解作用等),及目前在国内外市场销售的酸奶进行总结,为功能型酸奶的研发及工业化的生产提供理论基础。 相似文献
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Chunqiang WANG Chunjing LI Hongjiao LI Wei MA Shuxiong CHEN Yun ZHAO Jiahui RAO Xu ZHOU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1419-1425
Inhibins, as members of the transforming growth factor beta (TGF-β)
superfamily, downregulate the synthesis and secretion of follicle-stimulating hormone
(FSH) in an endocrine manner. The role of inhibin/betaglycan in the ovary regulation
recently gained attention. To date, no data exist on the function of inhibin α subunit and
betaglycan in cystic follicles. In this study, the expressions of inhibin α subunit and
betaglycan in cystic follicles were investigated using immunohistochemistry, real-time PCR
and Western blot analysis. Both inhibin α subunit and betaglycan immunoreactivities were
mainly localized in the granulosa cells of follicles. Expression of inhibin α subunit and
betaglycan was inferior in cystic follicles compared with that in normal large follicles.
However, the result of enzyme-linked immunosorbent assay showed no significant difference
in the decreasing in concentration of inhibin α subunit in cystic follicular fluid
compared with the control (P>0.05). In this study, we explored the
effects of FSH on betaglycan expression in granulosa cells in vitro. As
expected, a significant increase in the expressions of betaglycan mRNA and protein in
granulosa cells was observed in response to exogenous FSH (30
ng/ml) (P<0.05) compared with the
control. Consequently, this study provides evidence that the expressions of inhibin α
subunit and betaglycan are inferior in cystic follicles, and this may be caused by the
decrease in FSH in the presence of a cystic follicle. 相似文献
125.
提出畜牧业产业化经营的发展是畜牧业产业化经营产业链各成员之间利益生成和分配的合作与博弈过程,产业链是否稳定决定于利益分配是否合理,产业链各成员是否实现了个体利益分配的最优化,从而实现产业链效益的最大化。指出广东畜牧业产业化经营的健康发展离不开产业链利益生成和分配机制的不断优化,离不开市场的导向作用、法律制度的完善和政府的宏观调控作用。 相似文献
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春秋兼用家蚕新品种“春华×秋实”的育成 总被引:1,自引:4,他引:1
以丝质优、耐氟污染性能较强的品种为育种材料,采用常规杂交育种方法,育成一对春秋兼用的中丝量家蚕新品种春华×秋实。浙江省蚕品种实验室共同鉴定和农村试养鉴定表明该品种具有以下特点:孵化、眠起、老熟齐一,体质强健好养,茧型较大,产量高;茧丝质优良,春期饲养茧层率23.46%,鲜茧出丝率17.54%,茧丝长1 263 m,解舒率83.52%,纤度2.773 dtex,洁净94.50分;综合经济性状优良,与对照品种菁松×皓月相比,万蚕产茧量提高7.0%,与对照品种秋丰×白玉相比,万蚕产茧量、万蚕茧层量、茧丝长、解舒丝长、鲜茧出丝率分别提高1.7%、8.9%、9.0%、6.6%、8.1%。新品种已通过浙江省农作物品种审定,适合在浙江省及长江中下游蚕区推广饲养。 相似文献