Abstract #T148
Section: Lactation Biology (posters)
Session: Lactation Biology II
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
Session: Lactation Biology II
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
# T148
Increasing the availability of Thr, Ile, Val, and Leu relative to Lys while maintaining an ideal ratio of Lys:Met alters bovine mammary cell transcriptome profiles measured by RNA-sequencing.
Xianwen Dong1,2, Zheng Zhou*3, Ariane Helmbrecht4, Claudia Parys4, Z. Wang2, Juan J. Loor1, 1University of Illinois, Urbana, IL, 2Sichuan Agricultural University, Ya’an, Sichuan Province, China, 3Clemson University, Clemson, SC, 4Evonik Nutrition & Care GmbH, Hanau-Wolfgang, Germany.
Key Words: transcriptome, mTOR, amino acid
Increasing the availability of Thr, Ile, Val, and Leu relative to Lys while maintaining an ideal ratio of Lys:Met alters bovine mammary cell transcriptome profiles measured by RNA-sequencing.
Xianwen Dong1,2, Zheng Zhou*3, Ariane Helmbrecht4, Claudia Parys4, Z. Wang2, Juan J. Loor1, 1University of Illinois, Urbana, IL, 2Sichuan Agricultural University, Ya’an, Sichuan Province, China, 3Clemson University, Clemson, SC, 4Evonik Nutrition & Care GmbH, Hanau-Wolfgang, Germany.
The objective of this experiment was to determine if varying the ratio of Lys:Thr, Lys:Ile, Lys:Val, and Lys:Leu while maintaining an ideal ratio of Lys:Met and a fixed ratio of other essential AA (IPAA) elicits changes in mammary cell transcriptome profiles. MAC-T cells were incubated for 12 h (n = 5 replicates/treatment) with IPAA (2.9:1 Lys:Met; 1.8:1 Lys:Thr; 2.38:1 Lys:His; 1.23:1 Lys:Val; 1.45:1 Lys:Ile; 0.85:1 Lys:Leu; 2.08:1 Lys:Arg) or IPAA supplemented with Thr, Ile, Val, Leu to achieve a Lys:Thr 1.3:1 (LT1.3), Lys:Ile 1.29:1 (LI1.29), Lys:Val 1.12:1 (LV1.12), or Lys:Leu 0.78:1 (LL0.78). Extracted total RNA was sequenced using the Illumina platform, and mapped to the Bos taurus genome assembly (UMD_3.1.1). Cellular protein was extracted for Western blot to examine phosphorylation status of mTORC1 pathway components. Statistical analysis was conducted using the Bioconductor edgeR package, with treatment as fixed effect. The Dynamic Impact Approach software was used to uncover the most-impacted cellular pathways. Compared with IPAA, ANOVA at P value <0.05 identified 1730, 1188, 907, and 799 differentially expressed genes (DEG) in response to LL0.78, LV1.12, LI1.29, and LT1.3, respectively. When compared with IPAA, the bioinformatics analysis revealed unique responses to treatments, including an overall upregulation of sulfur metabolism and glycosphingolipid metabolism with LL0.78, upregulation of butirosin and neomycin synthesis and retinol metabolism with LV1.12, and upregulation of ubiquinone biosynthesis with LT1.3. In contrast, LI1.29 resulted in downregulation of cytochrome P450 and glutathione metabolism among the top-impacted pathways. Combined with the greatest phosphorylation status of AKT, mTORC1, and RPS6 in response to LV1.12, the transcriptome data underscored a potentially unique role of enhanced Val supply on mammary cell protein synthesis and cellular function. Overall, data indicate that enhancing the supply of Thr, Ile, Val, and Leu when Lys:Met is at the ideal ratio can alter mammary transcriptome profiles to various extents. The significance of these alterations to mammary cell function in vivo remain to be determined.
Key Words: transcriptome, mTOR, amino acid
