Cellular and Molecular Anatomy of the Human Neuromuscular Junction

This is the final version of the article. Available from Elsevier via the DOI in this record.The neuromuscular junction (NMJ) plays a fundamental role in transferring information from lower motor neuron to skeletal muscle to generate movement. It is also an experimentally accessible model synapse routinely studied in animal models to explore fundamental aspects of synaptic form and function. Here, we combined morphological techniques, super-resolution imaging, and proteomic profiling to reveal the detailed cellular and molecular architecture of the human NMJ. Human NMJs were significantly smaller, less complex, and more fragmented than mouse NMJs. In contrast to mice, human NMJs were also remarkably stable across the entire adult lifespan, showing no signs of age-related degeneration or remodeling. Super-resolution imaging and proteomic profiling revealed distinctive distribution of active zone proteins and differential expression of core synaptic proteins and molecular pathways at the human NMJ. Taken together, these findings reveal human-specific cellular and molecular features of the NMJ that distinguish them from comparable synapses in other mammalian species.This work was supported by small project grant funding from Biomedical Sciences (Anatomy) at the University of Edinburgh (T.H.G. and R.A.J.), the Darwin Trust of Edinburgh (M.L.H.), and the BBSRC (Institute Strategic Programme Funding; T.M.W., S.L.E., and L.C.G.)

Germination and seedling vigour of hydroprimed stored seeds of African eggplant (Solanum macrocarpon L.) produced under different nitrogen fertilizer rates

The study was conducted in the laboratory and screen house of School of Agriculture and Agricultural Technology, Federal University of Technology, Minna, Niger state, Nigeria. Effects of two factors- nitrogen fertilizer application to the mother plant at 0, 20, 40, 60, 80, 100 kg ha-1 and hydropriming (hydro-primed and non-hydroprimed) on Solanum marcrocarpon (cv. FUTMSm-2) seed quality were tested during a storage period of 16 weeks. The laboratory study used a 6 x 2 factorial experiment which was subjected to a completely randomized design. Data were collected on 100-seed weight, changes in moisture content during storage, germination percentage, seedling length, seedling shoot and root length. Data collected on all parameters were subjected to analysis of variance using statistical analysis system (SAS) and means were separated using Duncan’s multiple range test (DMRT) where significant differences occurred among treatments. Seeds produced with 60 kg N ha-1 were the heaviest while seeds produced without N application was the lightest. Moisture content increased with storage period. Germination percentages were low (about 1 to 10%) at 0 to 2 weeks after storage (WAS) at all N fertilizer rates. Impressive increase in values from about 57% ( at 0 kg N ha-1) to 87% ( at 80 kg N ha-1) were recorded between 4 and 10 WAS. The highest germination percentage of about 89 was obtained at 80 kg N ha-1 while the poorest was recorded at 0 kg N ha-1. Viability was best maintained in seeds produced with 80 kg N ha-1 as germination percentage of 79% was still recorded at 12 WAS as against a range of 31-56% for other N treatments. Hydropriming resulted in enhanced seed germination. Seedlings from seeds produced with application of 80 or 100 kg N ha-1 were generally significantly longer than those produced with 0 kg N ha-1. Root length values were significantly greater in seeds produced with 100 kg N ha-1 compared with the values recorded with 0 kg N ha-1. No consistent trends were established in respect of shoot length. Hydropriming only resulted in significant increase in seedling length at 8 and 16 WAS and in root length at 0, 8 and 16 WAS. Hydropriming did not significantly influence shoot length. It is concluded that application of nitrogen fertilizer at 80 kg ha-1 resulted in the production of best quality seed and that hydropriming enhanced seed germination and seedling growth.Key words: Solanum macrocarpon, seed moisture content, seed quality, hydropriming, seedling vigour, seed dormanc