Growing evidence implicates impairment of autophagy as a candidate pathogenic mechanism in the spectrum of neurodegenerative disorders which includes amyotrophic lateral sclerosis and frontotemporal lobar degeneration (ALS-FTLD). SQSTM1, which encodes the autophagy receptor SQSTM1/p62, is genetically associated with ALS-FTLD, although to date autophagy-relevant functional defects in disease-associated variants have not been described. A key protein-protein interaction in autophagy is the recognition of a lipid-anchored form of LC3 (LC3-II) within the phagophore membrane by SQSTM1, mediated through its LC3-interacting region (LIR), and notably some ALS-FTLD mutations map to this region. Here we show that although representing a conservative substitution and predicted to be benign, the ALS-associated L341V mutation of SQSTM1 is defective in recognition of LC3B. We place our observations on a firm quantitative footing by showing the L341V-mutant LIR is associated with a ∼3-fold reduction in LC3B binding affinity and using protein NMR we rationalize the structural basis for the effect. This functional deficit is realized in motor neuron-like cells, with the L341V mutant EGFP-mCherry-SQSTM1 less readily incorporated into acidic autophagic vesicles than the wild type. Our data supports a model in which the L341V mutation limits the critical step of SQSTM1 recruitment to the phagophore. The oligomeric nature of SQSTM1, which presents multiple LIRs to template growth of the phagophore, potentially gives rise to avidity effects which amplify the relatively modest impact of any single mutation on LC3B binding. Over the lifetime of a neuron, impaired autophagy could expose a vulnerability, which ultimately tips the balance from cell survival toward cell death.

Anionic polymerization of N,N‐disubstituted acrylamides in hydrocarbon media is stereospecific and yields a new series of crystalline tactic polymers containing polar groups. These tactic polymers melt above 300°C. and have different solubilities from the atactic isomers. There are also differences in the rates of hydrolysis and infrared spectra. The presence of ethers in the polymerization lowers both the tacticity of the product and its molecular weight. A heterogeneous surface is not necessary for stereospecificity, and, in cases where monomer and initiator are soluble in hydrocarbons, the reaction is homogeneous throughout.

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The conversion of readily available monosaccharides to high-value amino alcohols using a key biocatalytic step is an attractive strategy for the preparation of these chiral synthons. Here, we report a previously undescribed example of the direct amination of monosaccharides, which exist predominantly in their cyclic form at equilibrium, using amine transaminase biocatalysts, providing access to a panel of amino alcohols in moderate to high conversion and isolated yield. A recently developed high-throughput colorimetric screen, employing o-xylylenediamine, was initially used to identify amine transaminase enzymes displaying this activity towards cyclic sugars and reactions were successfully scaled-up using isopropylamine.