02431naa a2200289 a 450000100080000000500110000800800410001902400520006010000200011224501640013226000090029650000180030552015890032365000180191265000150193065000100194565000110195565000140196665000190198065000160199965000170201570000180203270000180205070000260206870000190209477300280211321631112024-03-25       2024    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s00335-024-10030-x2DOI1 aCARVALHO, W. A.  aGenetic factors underlying host resistance to Rhipicephalus microplus tick infestation in Braford cattleba systems biology perspective.h[electronic resource]  c2024  aFirst online.  aApproximately 80% of the world's cattle are raised in regions with a high risk of tick-borne diseases, resulting in significant economic losses due to parasitism by Rhipicephalus(Boophilus)microplus. However, the lack of a systemic biology approach hampers a comprehensive understanding of tick-host interactions that mediate tick resistance phenotypes. Here, we conducted a genome-wide association study (GWAS) of 2933 Braford cattle and found 340 single-nucleotide polymorphisms (SNPs) associated with tick counts. Gene expression analyses were performed on skin samples obtained from previously tick-exposed heifers with extremely high or low estimated breeding values for R.microplus counts. Evaluations were performed both before and after artificial infestation with ticks. Differentially expressed genes were found within 1-Mb windows centered at significant SNPs from GWAS. A total of 330 genes were related to the breakdown of homeostasis that was induced by larval attachment to bovine skin. Enrichment analysis pointed to a key role of proteolysis and signal transduction via JAK/STAT, NFKB and WNT/beta catenin signaling pathways. Integrative analysis on matrixEQTL revealed two cis-eQTLs and four significant SNPs in the genes peptidylargininedeiminasetypeIV (PADI4) and LOC11449251. The integration of genomic data from QTL maps and transcriptome analyses has identified a set of twelve key genes that show significant associations with tick loads. These genes could be key candidates to improve the accuracy of genomic predictions for tick resistance in Braford cattle.  aAmber disease  aParasitism  aTicks  aBovino  aCarrapato  aDoença Animal  aParasitismo  aResistência1 aGASPAR, E. B.1 aDOMINGUES, R.1 aREGITANO, L. C. de A.1 aCARDOSO, F. F.  tMammalian Genome, 2024.