ULK1 and ULK2 Regulate Stress Granule Disassembly Through Phosphorylation and Activation of VCP/p97.

Disturbances in autophagy and stress granule dynamics have been implicated as potential mechanisms underlying inclusion body myopathy (IBM) and related disorders. Yet the roles of core autophagy proteins in IBM and stress granule dynamics remain poorly characterized. Here, we demonstrate that disrupted expression of the core autophagy proteins ULK1 and ULK2 in mice causes a vacuolar myopathy with ubiquitin and TDP-43-positive inclusions; this myopathy is similar to that caused by VCP/p97 mutations, the most common cause of familial IBM. Mechanistically, we show that ULK1/2 localize to stress granules and phosphorylate VCP, thereby increasing VCP's activity and ability to disassemble stress granules. These data suggest that VCP dysregulation and defective stress granule disassembly contribute to IBM-like disease in Ulk1/2-deficient mice. In addition, stress granule disassembly is accelerated by an ULK1/2 agonist, suggesting ULK1/2 as targets for exploiting the higher-order regulation of stress granules for therapeutic intervention of IBM and related disorders.

An inhibitory compound produced by a soil isolate of Rhodococcus has strong activity against the veterinary pathogen R. equi.

Complete genome sequencing of dozens of strains of the soil bacterium Rhodococcus has revealed the presence of many cryptic biosynthetic gene clusters, presumably dedicated to the production of small molecules. This has sparked a renewed interest in this underexplored member of the Actinobacteria as a potential source of new bioactive compounds. Reported here is the discovery of a potent inhibitory molecule produced by a newly isolated strain of Rhodococcus, strain MTM3W5.2. This small inhibitory molecule shows strong activity against all Rhodococcus species tested, including the veterinary pathogen R. equi, and some closely related genera. It is not active against other Gram positive or Gram negative bacteria. A screen of random transposon mutants identified a gene required to produce this inhibitory compound. This gene is a large multi-domain, type I polyketide synthase that is part of a very large multi-gene biosynthetic gene cluster in the chromosome of strain MTM3W5.2. The high resolution mass spectrum of a major chromatogram peak from a broth culture extract of MTM3W5.2 shows the presence of a compound at m/z 911.5490 atomic mass units. This compound is not detected in the culture extracts from a non-producing mutant strain of MTM3W5.2. A large gene cluster containing at least 14 different type I polyketide synthase genes is proposed to be required to synthesize this antibiotic-like compound.

The COPII cargo adapter SEC24C is essential for neuronal homeostasis.

SEC24 family members are components of the coat protein complex II (COPII) machinery that interact directly with cargo or with other adapters to ensure proper sorting of secretory cargo into COPII vesicles. SEC24C is 1 of 4 mammalian SEC24 paralogs (SEC24A-D), which segregate into 2 subfamilies on the basis of sequence homology (SEC24A/SEC24B and SEC24C/SEC24D). Here, we demonstrate that postmitotic neurons, unlike professional secretory cells in other tissues, are exquisitely sensitive to loss of SEC24C. Conditional KO of Sec24c in neural progenitors during embryogenesis caused perinatal mortality and microcephaly, with activation of the unfolded protein response and apoptotic cell death of postmitotic neurons in the murine cerebral cortex. The cell-autonomous function of SEC24C in postmitotic neurons was further highlighted by the loss of cell viability caused by disrupting Sec24c expression in forebrain neurons of mice postnatally and in differentiated neurons derived from human induced pluripotent stem cells. The neuronal cell death associated with Sec24c deficiency was rescued in knockin mice expressing Sec24d in place of Sec24c. These data suggest that SEC24C is a major cargo adapter for COPII-dependent transport in postmitotic neurons in developing and adult brains and that its functions overlap at least partially with those of SEC24D in mammals.

Power wheelchair prescription, utilization, satisfaction, and cost for patients with amyotrophic lateral sclerosis: preliminary data for evidence-based guidelines.

OBJECTIVES: To determine the features most frequently selected in a power wheelchair (PWC), level of satisfaction with the selections, and how often the PWC features are used by patients diagnosed with amyotrophic lateral sclerosis (ALS)/motor neuron disease (MND). DESIGN: Internally generated questionnaire. SETTING: An ALS/Muscular Dystrophy Association center. PARTICIPANTS: Convenience sample of current patients (N=45) of our clinic with ALS/MND who are PWC users (men, n=27; women, n=18; age range, 27-85 y). INTERVENTION: Self-administered survey. MAIN OUTCOME MEASURE: Thirty-two patients completed a 31-question survey investigating patients' patterns of selection, satisfaction, and frequency of PWC use; technical and psychometric influences; and other aspects of decision-making processes that patients experience before, during, and after acquiring a PWC. RESULTS: Ninety percent of respondents received their evaluations at a multidisciplinary ALS clinic, 1 via the Department of Veterans Affairs, and 1 was unknown. Sixty-six percent of patients thought the chair evaluation was timed correctly, and 19% wished they had started sooner. Forty-five percent of people were able to walk a few steps, and 55% were able to stand when their chairs arrived. When they first received the chair, 79% were satisfied with the overall comfort of the chair, and 86% were satisfied with the ease of use; currently, 69% are satisfied with the overall comfort, and 72% are satisfied with ease of use. There was a statistically significant difference in how patients used their wheelchair features initially and currently in terms of seat elevate and attendant control, but not tilt, recline, and elevating leg rests. The average cost for the power chairs was $26,404 (range, $19,376-$34,311), and the average cost a month is $917. Overall, 88% of respondents said they would get the same type of chair with the same features again, and 81% felt that the chair was a good value for the cost. CONCLUSIONS: We obtained first-hand knowledge from 32 patients with ALS/MND who are current PWC users on their use and satisfaction with their PWCs from initial to current use. Based on this survey, patients with ALS/MND seen for their wheelchair evaluation with experienced clinicians exhibit high use and satisfaction with their PWCs.