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991.
Claudia Travaglia Ana C. Cohen Herminda Reinoso Carlos Castillo Rubén Bottini 《Journal of Plant Growth Regulation》2007,26(3):285-289
This work investigates the effects of abscisic acid (ABA) on physiologic parameters related to yield in wheat (Triticum aestivum) grown under field conditions with water restriction ranging between 45.7% and 49.5% of field capacity during anthesis and
postanthesis. ABA (300 mg L−1) was sprayed onto the plants at the beginning of shoot lengthening which significantly promoted leaf area and higher concentrations
of chlorophylls and carotenoids in flag leaf at anthesis. ABA also increased soluble carbohydrates in shoots at anthesis,
which were then re-exported to the grains at maturity. This correlated with a yield increase that was achieved by a higher
number and weight of grains per spike, but protein content was not significantly affected. 相似文献
992.
Misha Golynskiy Sheng Li Virgil L. WoodsJr Seth M. Cohen 《Journal of biological inorganic chemistry》2007,12(5):699-709
The manganese transport regulator (MntR) of Bacillus subtilis is a metalloregulatory protein responsible for regulation of genes involved in manganese uptake by this organism. MntR belongs
to the iron-responsive DtxR family, but is allosterically regulated by manganese and cadmium ions. Having previously characterized
the metal binding affinities of this protein as well as the DNA-binding activation profiles for the relevant metal ions, we
have focused the current study on investigating the structural changes of MntR in solution upon binding divalent transition
metal ions. Deuterium exchange mass spectrometry was utilized to investigate the deuterium exchange dynamics between apo-MntR,
Co2+-MntR, Cd2+-MntR, and Mn2+-MntR. Comparing the rates of deuteration of each metal-bound form of MntR reveals that the N-terminal DNA-binding motif is
more mobile in solution than the C-terminal dimerization domain. Furthermore, significant protection from deuterium exchange
is observed in the helices that contribute metal-chelating amino acids to form the metal binding site of MntR. In contrast,
the bulk of the DNA-binding winged helix–turn–helix motif shows no difference in deuterium exchange upon metal binding. Mapping
of the deuteration patterns onto the crystal structures of MntR yields insight into how metal binding affects the protein
structure and complements earlier studies on the mechanism of MntR. Metal binding acts to rigidify MntR, thereby limiting
the mobility of the protein and reducing the entropic cost of DNA binding.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Many lesions associated with aging have been well-characterized in various strains of rats. Although documented in Sprague-Dawley and spontaneously hypertensive rats, polyarteritis nodosa has not previously been reported in ACI/SegHsd rats. ACII SegHsd rats were maintained on high-fat (40.5%), low-fat (11.6%), and high-fat to low-fat dietary protocols to examine the correlation between dietary fat and the regulation of prostate 5alpha-reductase gene expression and prostate cancer. Seven rats died unexpectedly with hemoabdomen and rupture of the pancreaticoduodenal artery secondary to polyarteritis nodosa (PAN). The purpose of this study was to analyze the pathologic findings in these and the remaining ACI/SegHsd rats and to correlate the level of dietary fat with the presence of PAN, arterial rupture, and hemoabdomen. Approximately 65% of the rats had evidence of PAN by histopathology, with a 24% incidence of arterial rupture. Additional lesions noted included an 88% incidence of chronic progressive nephropathy (CPN) and a 32% incidence of cartilaginous foci in the aortic valve. We found no association between the percentage of dietary fat and incidence of PAN, CPN, or cardiac cartilage. Although arterial rupture is a known complication of polyarteritis nodosa in humans, this case series is the first to document arterial rupture and hemoabdomen in rats with PAN. 相似文献
995.
Choudhury Amir Sohail Choudhury Parthankar Gassah Rejoice 《Primates; journal of primatology》2022,63(2):173-184
Primates - The Bengal slow loris (Nycticebus bengalensis) is an endangered nonhuman primate distributed in Southeast Asia, including India. The species is facing sharp population decline throughout... 相似文献
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