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Introduction: Muscle glycolytic potential (GP) is a key factor affecting multiple meat quality traits. It is calculated based on the contents of residual glycogen and glucose (RG), glucose-6-phosphate (G6P), and lactate (LAT) contents in muscle. However, the genetic mechanism of glycolytic metabolism in skeletal muscle of pigs remains poorly understood. With a history of more than 400 years and some unique characteristics, the Erhualian pig is called the “giant panda” (very precious) in the world’s pig species by Chinese animal husbandry.Methods: Here, we performed a genome-wide association study (GWAS) using 1.4M single nucleotide polymorphisms (SNPs) chips for longissimus RG, G6P, LAT, and GP levels in 301 purebred Erhualian pigs.Results: We found that the average GP value of Erhualian was unusually low (68.09 μmol/g), but the variation was large (10.4–112.7 μmol/g). The SNP-based heritability estimates for the four traits ranged from 0.16–0.32. In total, our GWAS revealed 31 quantitative trait loci (QTLs), including eight for RG, nine for G6P, nine for LAT, five for GP. Of these loci, eight were genome-wide significant (p < 3.8 × 10−7), and six loci were common to two or three traits. Multiple promising candidate genes such as FTO, MINPP1, RIPOR2, SCL8A3, LIFR and SRGAP1 were identified. The genotype combinations of the five GP-associated SNPs also showed significant effect on other meat quality traits.Discussion: These results not only provide insights into the genetic architecture of GP related traits in Erhualian, but also are useful for pig breeding programs involving this breed.

N6-acetyl-L-lysine residue is abundant in dietary protein but less is known about its potential influences on the diet-consumers. We herein report that N6-acetyl-L-lysine residues in acetylated dietary protein directly contributes to the acetylome in animal. By feeding mice with deuterium-labelled N6-acetyl-L-lysine-proteins, we demonstrated that acetylated dietary protein is a direct source of N6-acetyl-L-lysine that can widely contribute the acetylome in organs of liver, brain, and lung in mice. In mammalian cells, N6-acetyl-L-lysine can be utilized by Lysyl-tRNA synthetase (KARS) to generate N6-acetyl-L-lysyl-tRNA, which introduces N6-acetyl-L-lysine into the growing nascent polypeptide and intra-translationally results in protein acetylation. Co-crystal structure of KARS in complex with N6-acetyl-L-lysyl-AMP and pyrophosphate, coupled with in vitro biochemical assays, further confirms a sequential mechanism that KARS produces N6-acetyl-L-lysyl-AMP and transfers the N6-acetyl-L-lysyl-moiety to lysine cognate tRNA to generate N6-acetyl-L-lysyl-tRNA. Together, the present study establishes a model that N6-acetyl-L-lysine bridges the influence of acetylated dietary protein to the acetylome in dietary protein-consumer. Importantly, an undocumented mechanism that intra-translationally deposit acetylation in nascent proteins has been proved. It might extend the repertoire of acetylome and improves our understandings in protein modification modes in cells.

The flexural wave propagation in a grillage structure with a propagating disturbance is studied firstly by the use of the multi-reflection method. The grillage structure consists of many beams intersecting each other at right angles. Each periodic binary beam consists of a finite repetition of alternating material A and material B. A propagating wave is incident upon a discontinuity of a beam along the x axis and gives rise to transmitted and reflected waves. Here all of the transmitted and reflected waves of given flexural wave incident upon the beam at some specified location are found and superposed, these waves travel to the other beams as a bending wave in the direction of their partially reflected and partially transmitted. Then the wave-fields of two beams along the y axis closest to external disturbance is set up, these two beams only need to consider the influence of bending waves on the x-beams on them. Next the wave-fields of two beams along the x axis closest to external disturbance is set up, the rest can be done in the same manner. Finally the wave-field of any beam at some specified location can be determined.