Reconstitution of UCP1 using CRISPR/Cas9 in the white adipose tissue of pigs decreases fat deposition and improves thermogenic capacity

Abstract

Uncoupling protein 1 (UCP1) is localized on the inner mitochondrial membrane and generates heat by uncoupling ATP synthesis from proton transit across the inner membrane. UCP1 is a key element of nonshivering thermogenesis and is most likely important in the regulation of body adiposity. Pigs (Artiodactyl family ) lack a functional UCP1 gene, resulting in poor thermoregulation and susceptibility to cold, which is an economic and pig welfare issue owing to neonatal mortality. Pigs also have a tendency toward fat accumulation, which may be linked to their lack of UCP1, and thus influences the efficiency of pig production. Here, we report application of a CRISPR/Cas9-mediated, homologous recombination (HR)-independent approach to efficiently insert mouse adiponectin-UCP1 into the porcine endogenous locus. The resultant UCP1 knock-in (KI) pigs showed an improved ability to maintain body temperature during acute cold exposure, but they did not have alterations in physical activity levels or total daily energy expenditure (DEE). Furthermore, ectopic UCP1 expression in white adipose tissue (WAT) dramatically decreased fat deposition by 4.89% ( < 0.01), consequently increasing carcass lean percentage (CLP; < 0.05). Mechanism studies indicated that the loss of fat upon UCP1 activation in WAT was linked to elevated lipolysis. UCP1 KI pigs are a potentially valuable resource for agricultural production through their combination of cold adaptation, which improves pig welfare and reduces economic losses, with reduced fat deposition and increased lean meat production.

FGF21 decreases food intake and body weight in obese Göttingen minipigs

“…36 Furthermore, lack of UCP-1 in pigs may also affect body composition. 37 In the present study, we found that FGF21 treatment improved glucose tolerance and increased insulin sensitivity. Notably, the acute blood glucose-lowering effect of FGF21 is abolished in UCP-1 knockout mice, 38 indicating UCP-1 involvement in the mechanism.…”

“…Unfortunately, knowledge regarding the effect of food restriction on body composition in obese minipigs is limited, but in humans, the percentage of total weight loss comprising fat free mass varies from 4% to 53%, depending on the intervention . Furthermore, lack of UCP‐1 in pigs may also affect body composition …”

Protein kinase D1 deletion in adipocytes enhances energy dissipation and protects against adiposity

“…Although we did not observe a clear correlation between the absence of PKD1 and appearance of multilocular cells within subcutaneous depot of adipose tissue, the protein abundance of UCP1 was clearly elevated in the absence of PKD1. Of note, in several other mouse models, increased UCP1 abundance was observed in unilocular adipocytes (Rossmeisl et al , ; Schneider et al , ; Zheng et al , ). However, in isolated PKD1‐deficient adipocytes we observed elevated gene expression of Adrb3, but Ucp1 levels were not altered at basal conditions.…”

An Overview of Mitigation and Adaptation Needs and Strategies for the Livestock Sector

“…However, whether and how this translates to adaptation strategies for domestic poultry production remains to be explored. Zheng et al (2017) [26] find that genetic trait modification can decrease low-temperature susceptibility and that there is substantial potential to explore this, as CC portends changes but there has been little recent work on animal climate resilience.…”