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  • Mccullough posted an update 7 months, 3 weeks ago

    Suppression of GRFs function by overexpressing microRNA396a caused an accumulation of photochlorophyllide in the dark and severe photobleaching upon light exposure. Additionally, BZR1, PIF4 and GRF7 interact with each other and precisely regulate the expression of chlorophyll biosynthetic genes. Our findings reveal an essential role for BRs in promoting seedling development and survival during the initial emergence of seedlings from subterranean darkness into sunlight.Cell wall assembly requires harmonized deposition of cellulose and matrix polysaccharides. Cortical microtubules orient the deposition of cellulose by guiding the trajectory of cellulose synthase complexes. Vesicles containing matrix polysaccharides are thought to be transported by the FRA1 kinesin to facilitate their secretion along cortical microtubules. The cortical microtubule cytoskeleton thus may provide a platform to coordinate the delivery of cellulose and matrix polysaccharides, but the underlying molecular mechanisms remain unknown. Here, we show that the tail region of the FRA1 kinesin physically interacts with CMU proteins that are important for the microtubule-dependent guidance of cellulose synthase complexes. Interaction with CMUs did not affect microtubule binding or motility of the FRA1 kinesin but differentially affected the protein levels and microtubule localization of CMU1 and CMU2, thus regulating the lateral stability of cortical microtubules. Phosphorylation of the FRA1 tail region inhibited binding to CMUs and consequently reversed the extent of cortical microtubule decoration by CMU1 and CMU2. Genetic experiments demonstrated the significance of this interaction to the growth and reproduction of Arabidopsis thaliana plants. We propose that modulation of CMU protein levels and microtubule localization by FRA1 provides a mechanism to stabilize the sites of deposition of both cellulose and matrix polysaccharides.Background CKD is associated with higher health care costs that increase with disease progression. However, research is lacking on the type of health care costs associated with CKD across all stages in a general population with a substantial comorbidity burden. Methods Using electronic medical records of an integrated delivery system, we evaluated health care costs by expenditure type in general and in patients with CKD by eGFR and presence of comorbidities. We categorized 146,132 patients with eGFR data in 2016 or 2017 and examined nonmutually exclusive groups according to presence of diabetes mellitus, cardiovascular disease, or heart failure. We used 1 year of follow-up data to calculate outpatient, inpatient, emergency, pharmaceutical, dialysis, and total health care costs by eGFR (Kidney Disease Improving Global Outcomes-defined eGFR categories), adjusted for age, sex, and nonwhite race. Results Mean total health care costs among patients with CKD without comorbidities were 31% higher than among patients without CKD ($7374 versus $5631, respectively). Hospitalizations accounted for 35% of total costs among those with CKD and no comorbidities but up to 55% among patients with CKD and heart failure. The proportion of costs attributable to hospitalizations accelerated with declining kidney function, reaching as high as 66%. Conclusions Poorer kidney function and the presence of diabetes mellitus, cardiovascular disease, or heart failure drive substantial health care costs and increase the proportion of costs attributable to inpatient care. The large contribution of inpatient costs begins in earlier stages of CKD and escalates as kidney function declines. Additional therapies to reduce CKD incidence, slow CKD progression, and lower hospitalization risk are needed to benefit patients and reduce CKD’s economic burden.Background Neutrophil gelatinase-associated lipocalin (NGAL) is a diagnostic marker of intrinsic kidney injury produced by damaged renal cells and by neutrophils. DMAMCL in vivo ANCA-associated vasculitis features necrotizing crescentic GN (NCGN), and ANCA-activated neutrophils contribute to NCGN. Whether NGAL plays a mechanistic role in ANCA-associated vasculitis is unknown. Methods We measured NGAL in patients with ANCA-associated vasculitis and mice with anti-myeloperoxidase (anti-MPO) antibody-induced NCGN. We compared kidney histology, neutrophil functions, T cell proliferation and polarization, renal infiltrating cells, and cytokines in wild-type and NGAL-deficient chimeric mice with anti-MPO antibody-induced NCGN. To assess the role of TH17 immunity, we transplanted irradiated MPO-immunized MPO-deficient mice with bone marrow from either wild-type or NGAL-deficient mice; we also transplanted irradiated MPO-immunized MPO/IL-17A double-deficient mice with bone marrow from either IL-17A-deficient or NGAL/IL-17A double-dil, NGAL protects from ANCA-induced NCGN by downregulating TH17 immunity.Background The physiologic role of renomedullary interstitial cells, which are uniquely and abundantly found in the renal inner medulla, is largely unknown. Endothelin A receptors regulate multiple aspects of renomedullary interstitial cell function in vitro. Methods To assess the effect of targeting renomedullary interstitial cell endothelin A receptors in vivo, we generated a mouse knockout model with inducible disruption of renomedullary interstitial cell endothelin A receptors at 3 months of age. Results BP and renal function were similar between endothelin A receptor knockout and control mice during normal and reduced sodium or water intake. In contrast, on a high-salt diet, compared with control mice, the knockout mice had reduced BP; increased urinary sodium, potassium, water, and endothelin-1 excretion; increased urinary nitrite/nitrate excretion associated with increased noncollecting duct nitric oxide synthase-1 expression; increased PGE2 excretion associated with increased collecting duct cyclooxygenase-1 expression; and reduced inner medullary epithelial sodium channel expression. Water-loaded endothelin A receptor knockout mice, compared with control mice, had markedly enhanced urine volume and reduced urine osmolality associated with increased urinary endothelin-1 and PGE2 excretion, increased cyclooxygenase-2 protein expression, and decreased inner medullary aquaporin-2 protein content. No evidence of endothelin-1-induced renomedullary interstitial cell contraction was observed. Conclusions Disruption of renomedullary interstitial cell endothelin A receptors reduces BP and increases salt and water excretion associated with enhanced production of intrinsic renal natriuretic and diuretic factors. These studies indicate that renomedullary interstitial cells can modulate BP and renal function under physiologic conditions.

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