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411.
Evolutionary conservation of the immediate-early gene ZENK 总被引:3,自引:0,他引:3
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Erin Paul Marissa Kielbasinski John M. Sedivy Carlos Murga-Zamalloa Hemant Khanna Jan E. Klysik 《Transgenic research》2010,19(4):691-701
Supv3L1 is an evolutionarily conserved helicase that plays a critical role in the mitochondrial RNA surveillance and degradation
machinery. Conditional ablation of Supv3L1 in adult mice leads to premature aging phenotypes including loss of muscle mass and adipose tissue and severe skin abnormalities.
To get insights into the spatial and temporal expression of Supv3L1 in the mouse, we generated knock-in and transgenic strains
in which an EGFP reporter was placed under control of the Supv3L1 native promoter. During development, expression of Supv3L1 begins at the blastocyst stage, becomes widespread and strong
in all fetal tissues and cell types, and continues during postnatal growth. In mature animals reporter expression is only
slightly diminished in most tissues and continues to be highly expressed in the brain, peripheral sensory organs, and testis.
Together, these data confirm that Supv3L1 is an important developmentally regulated gene, which continues to be expressed
in all mature tissues, particularly the rapidly proliferating cells of testes, but also in the brain and sensory organs. The
transgenic mice and cell lines derived from them constitute a valuable tool for the examination of the spatial and temporal
aspects of Supv3L1 promoter activity, and should facilitate future screens for small molecules that regulate Supv3L1 expression. 相似文献
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Claudio Sedivy Silvia Dorn Alex Widmer Andreas Müller 《Biological journal of the Linnean Society. Linnean Society of London》2013,108(1):35-54
Bees are extraordinarily diverse with respect to host plant choice and adaptation. Recent findings suggest that bee host range might be largely governed by evolutionary constraints related to pollen digestion or flower recognition and handling. In the present study, we applied phylogenetic inference to investigate whether such constraints underlie host plant choice in bees of the Annosmia‐Hoplitis group (Megachilidae) and to what extent these bees have evolved specialized adaptations for pollen collection. We demonstrate that most pollen specialist species exclusively exploit either Boraginaceae or Fabaceae, whereas all pollen generalists harvest pollen from both Boraginaceae and Fabaceae. The counterintuitive affinity towards these two plant families, which are neither closely related nor share similar flower morphologies, demonstrates that pollen host choice is considerably constrained in this group of bees. We hypothesize that this Boraginaceae‐Fabaceae paradox might be the result of (1) similar secondary metabolites in the pollen of both families; (2) metabolites that can be detoxified by the same physiological tools; or (3) similar pollen nutrient composition. Contrary to the widely held belief that specialized adaptations for pollen collection are rare among bees, such adaptations are common in the Annosmia‐Hoplitis bees, where they have evolved several times independently to exploit flowers of widely different morphologies. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ●● , ●●–●●. 相似文献
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