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901.
Hafenstein S Bowman VD Chipman PR Bator Kelly CM Lin F Medof ME Rossmann MG 《Journal of virology》2007,81(23):12927-12935
Many entero-, parecho-, and rhinoviruses use immunoglobulin (Ig)-like receptors that bind into the viral canyon and are required to initiate viral uncoating during infection. However, some of these viruses use an alternative or additional receptor that binds outside the canyon. Both the coxsackievirus-adenovirus receptor (CAR), an Ig-like molecule that binds into the viral canyon, and decay-accelerating factor (DAF) have been identified as cellular receptors for coxsackievirus B3 (CVB3). A cryoelectron microscopy reconstruction of a variant of CVB3 complexed with DAF shows full occupancy of the DAF receptor in each of 60 binding sites. The DAF molecule bridges the canyon, blocking the CAR binding site and causing the two receptors to compete with one another. The binding site of DAF on CVB3 differs from the binding site of DAF on the surface of echoviruses, suggesting independent evolutionary processes. 相似文献
902.
Orr A Dubé MP Marcadier J Jiang H Federico A George S Seamone C Andrews D Dubord P Holland S Provost S Mongrain V Evans S Higgins B Bowman S Guernsey D Samuels M 《PloS one》2007,2(8):e685
Schnyder crystalline corneal dystrophy (SCCD, MIM 121800) is a rare autosomal dominant disease characterized by progressive opacification of the cornea resulting from the local accumulation of lipids, and associated in some cases with systemic dyslipidemia. Although previous studies of the genetics of SCCD have localized the defective gene to a 1.58 Mbp interval on chromosome 1p, exhaustive sequencing of positional candidate genes has thus far failed to reveal causal mutations. We have ascertained a large multigenerational family in Nova Scotia affected with SCCD in which we have confirmed linkage to the same general area of chromosome 1. Intensive fine mapping in our family revealed a 1.3 Mbp candidate interval overlapping that previously reported. Sequencing of genes in our interval led to the identification of five putative causal mutations in gene UBIAD1, in our family as well as in four other small families of various geographic origins. UBIAD1 encodes a potential prenyltransferase, and is reported to interact physically with apolipoprotein E. UBIAD1 may play a direct role in intracellular cholesterol biochemistry, or may prenylate other proteins regulating cholesterol transport and storage. 相似文献
903.
The spread of industrial civilizations has been particularly traumatic for the last remaining hunter-gatherer societies. Manifestations
of this include expatriation from ancestral lands, sickness, poverty, and environmental degradation. Northern Australia has
been no exception despite remaining a stronghold of Aboriginal cultures and still containing vast areas of relatively intact
landscapes. Most Aboriginal people reside in remote settlements where they remain on the negative extreme of basic indicators
such as life expectancy and educational attainment. In addition, biodiversity declines are being documented from loss of Aboriginal
fire management and invasion by feral species. There has been little consideration of potential health, social, economic,
or environmental benefits of routinely hunting, gathering or being on their land. This reflects a Western philosophical position
that segregates land management and health policy, a view at odds with Aboriginal peoples’ testimony of the indivisibility
of people and land. Here we report perspectives from Arnhemland gathered through observation and unstructured and semistructured
interviews. Themes that emerged included the high level of detailed, complex knowledge of their traditionally owned lands,
the perceived urgency about passing this on to younger people, and the need that both land and people have for each other
for the well-being of both. Primary motivations for returning to traditional lands were gathering food, escaping from stresses,
and educating young people. The many barriers included no transport, family problems, frequent funerals, and other cultural
or family obligations. This work forms part of a larger transdisciplinary research program that aims to inform policy about
sustainable futures in northern Australia. 相似文献
904.
Björn Corleis Allison N. Bucsan Maud Deruaz Vladimir D. Vrbanac Antonella C. Lisanti-Park Samantha J. Gates Alice H. Linder Jeffrey M. Paer Gregory S. Olson Brittany A. Bowman Abigail E. Schiff Benjamin D. Medoff Andrew M. Tager Andrew D. Luster Shabaana A. Khader Deepak Kaushal Douglas S. Kwon 《Cell reports》2019,26(6):1409-1418.e5
905.
Sang Eun Jun Kiu-Hyung Cho Ji-Young Hwang Wael Abdel-Fattah Alexander Hammermeister Raffael Schaffrath John L. Bowman Gyung-Tae Kim 《Molecules and cells》2015,38(3):243-250
Patterning of the polar axis during the early leaf developmental stage is established by cell-to-cell communication between the shoot apical meristem (SAM) and the leaf primordia. In a previous study, we showed that the DRL1 gene, which encodes a homolog of the Elongator-associated protein KTI12 of yeast, acts as a positive regulator of adaxial leaf patterning and shoot meristem activity. To determine the evolutionally conserved functions of DRL1, we performed a comparison of the deduced amino acid sequence of DRL1 and its yeast homolog, KTI12, and found that while overall homology was low, well-conserved domains were presented. DRL1 contained two conserved plant-specific domains. Expression of the DRL1 gene in a yeast KTI12-deficient yeast mutant suppressed the growth retardation phenotype, but did not rescue the caffeine sensitivity, indicating that the role of Arabidopsis Elongator-associated protein is partially conserved with yeast KTI12, but may have changed between yeast and plants in response to caffeine during the course of evolution. In addition, elevated expression of DRL1 gene triggered zymocin sensitivity, while overexpression of KTI12 maintained zymocin resistance, indicating that the function of Arabidopsis DRL1 may not overlap with yeast KTI12 with regards to toxin sensitivity. In this study, expression analysis showed that class-I KNOX genes were downregulated in the shoot apex, and that YAB and KAN were upregulated in leaves of the Arabidopsis drl1-101 mutant. Our results provide insight into the communication network between the SAM and leaf primordia required for the establishment of leaf polarity by mediating histone acetylation or through other mechanisms. 相似文献
906.
D. Magnus Eklund Kimitsune Ishizaki Eduardo Flores-Sandoval Saya Kikuchi Yumiko Takebayashi Shigeyuki Tsukamoto Yuki Hirakawa Maiko Nonomura Hirotaka Kato Masaru Kouno Rishikesh P. Bhalerao Ulf Lagercrantz Hiroyuki Kasahara Takayuki Kohchi John L. Bowman 《The Plant cell》2015,27(6):1650-1669
The plant hormone auxin (indole-3-acetic acid [IAA]) has previously been suggested to regulate diverse forms of dormancy in both seed plants and liverworts. Here, we use loss- and gain-of-function alleles for auxin synthesis- and signaling-related genes, as well as pharmacological approaches, to study how auxin regulates development and dormancy in the gametophyte generation of the liverwort Marchantia polymorpha. We found that M. polymorpha possess the smallest known toolkit for the indole-3-pyruvic acid (IPyA) pathway in any land plant and that this auxin synthesis pathway mainly is active in meristematic regions of the thallus. Previously a Trp-independent auxin synthesis pathway has been suggested to produce a majority of IAA in bryophytes. Our results indicate that the Trp-dependent IPyA pathway produces IAA that is essential for proper development of the gametophyte thallus of M. polymorpha. Furthermore, we show that dormancy of gemmae is positively regulated by auxin synthesized by the IPyA pathway in the apex of the thallus. Our results indicate that auxin synthesis, transport, and signaling, in addition to its role in growth and development, have a critical role in regulation of gemmae dormancy in M. polymorpha. 相似文献
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