TY - JOUR
T1 - The RNA-binding protein LARP1 is dispensable for pancreatic β-cell function and mass
AU - Werneck-de-Castro, Joao Pedro
AU - Peçanha, Flavia Leticia Martins
AU - Silvestre, Diego Henrique
AU - Bernal-Mizrachi, Ernesto
N1 - Funding Information:
The authors declare no conflict of interest. We would like to appreciate the technical support provided by Portia Ritter and Pau Romaguera Llacer. The current studies were funded by the National Institute of Health (NIDDK) Grant R01-DK073716 and DK084236.
Publisher Copyright:
© 2021, The Author(s).
PY - 2021/12
Y1 - 2021/12
N2 - Mechanistic target of rapamycin complex 1 (mTORC1) deficiency or chronic hyperactivation in pancreatic β-cells leads to diabetes. mTORC1 complexes with La-related protein 1 (LARP1) to specifically regulate the expression of 5′ terminal oligopyrimidine tract (5′TOP) mRNAs which encode proteins of the translation machinery and ribosome biogenesis. Here we show that LARP1 is the most expressed LARP in mouse islets and human β-cells, being 2–4-fold more abundant than LARP1B, a member of the family that also interacts with mTORC1. Interestingly, β-cells from diabetic patients have higher LARP1 and LARP1B expression. However, specific deletion of Larp1 gene in β-cells (β-Larp1KO mice) did not impair insulin secretion and glucose metabolism in male and female mice. High fat or high branched-chain amino acid (BCAA) diets did not disturb glucose homeostasis compared to control littermates up to 8 weeks; BCAA diet slightly impaired glucose tolerance in the β-Larp1KO mice at 16 weeks. However, no differences in plasma insulin levels, non-fasting glycemia and β-cell mass were observed in the β-Larp1KO mice. In conclusion, LARP1 is the most abundant LARP in mouse islets and human β-cells, and it is upregulated in diabetic subjects. However, genetically disruption of Larp1 gene did not impact glucose homeostasis in basal and diabetogenic conditions, suggesting no major role for LARP1 in β-cells.
AB - Mechanistic target of rapamycin complex 1 (mTORC1) deficiency or chronic hyperactivation in pancreatic β-cells leads to diabetes. mTORC1 complexes with La-related protein 1 (LARP1) to specifically regulate the expression of 5′ terminal oligopyrimidine tract (5′TOP) mRNAs which encode proteins of the translation machinery and ribosome biogenesis. Here we show that LARP1 is the most expressed LARP in mouse islets and human β-cells, being 2–4-fold more abundant than LARP1B, a member of the family that also interacts with mTORC1. Interestingly, β-cells from diabetic patients have higher LARP1 and LARP1B expression. However, specific deletion of Larp1 gene in β-cells (β-Larp1KO mice) did not impair insulin secretion and glucose metabolism in male and female mice. High fat or high branched-chain amino acid (BCAA) diets did not disturb glucose homeostasis compared to control littermates up to 8 weeks; BCAA diet slightly impaired glucose tolerance in the β-Larp1KO mice at 16 weeks. However, no differences in plasma insulin levels, non-fasting glycemia and β-cell mass were observed in the β-Larp1KO mice. In conclusion, LARP1 is the most abundant LARP in mouse islets and human β-cells, and it is upregulated in diabetic subjects. However, genetically disruption of Larp1 gene did not impact glucose homeostasis in basal and diabetogenic conditions, suggesting no major role for LARP1 in β-cells.
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U2 - 10.1038/s41598-021-81457-4
DO - 10.1038/s41598-021-81457-4
M3 - Article
C2 - 33483593
AN - SCOPUS:85099839819
VL - 11
JO - Scientific Reports
JF - Scientific Reports
SN - 2045-2322
IS - 1
M1 - 2079
ER -