Breed and adaptive response modulate bovine peripheral blood cells' transcriptome.
BACKGROUND
Adaptive response includes a variety of physiological modifications to face changes in external or internal conditions and adapt to a new situation. The acute phase proteins (APPs) are reactants synthesized against environmental stimuli like stress, infection, inflammation.


METHODS
To delineate the differences in molecular constituents of adaptive response to the environment we performed the whole-blood transcriptome analysis in Italian Holstein (IH) and Italian Simmental (IS) breeds. For this, 663 IH and IS cows from six commercial farms were clustered according to the blood level of APPs. Ten extreme individuals (five APP+ and APP- variants) from each farm were selected for the RNA-seq using the Illumina sequencing technology. Differentially expressed (DE) genes were analyzed using dynamic impact approach (DIA) and DAVID annotation clustering. Milk production data were statistically elaborated to assess the association of APP+ and APP- gene expression patterns with variations in milk parameters.


RESULTS
The overall de novo assembly of cDNA sequence data generated 13,665 genes expressed in bovine blood cells. Comparative genomic analysis revealed 1,152 DE genes in the comparison of all APP+ vs. all APP- variants; 531 and 217 DE genes specific for IH and IS comparison respectively. In all comparisons overexpressed genes were more represented than underexpressed ones. DAVID analysis revealed 369 DE genes across breeds, 173 and 73 DE genes in IH and IS comparison respectively. Among the most impacted pathways for both breeds were vitamin B6 metabolism, folate biosynthesis, nitrogen metabolism and linoleic acid metabolism.


CONCLUSIONS
Both DIA and DAVID approaches produced a high number of significantly impacted genes and pathways with a narrow connection to adaptive response in cows with high level of blood APPs. A similar variation in gene expression and impacted pathways between APP+ and APP- variants was found between two studied breeds. Such similarity was also confirmed by annotation clustering of the DE genes. However, IH breed showed higher and more differentiated impacts compared to IS breed and such particular features in the IH adaptive response could be explained by its higher metabolic activity. Variations of milk production data were significantly associated with APP+ and APP- gene expression patterns.
Department of Agriculture, Food, Environment and Animal Science (DI4A), University of Udine, via delle Scienze 206, 33100 Udine, Italy.
Nataliya
0000-0001-8781-440X
N
Pošćić
Department of Agriculture, Food, Environment and Animal Science (DI4A), University of Udine, via delle Scienze 206, 33100 Udine, Italy.
Tommaso
T
Montanari
Department of Agricultural, Environmental and Food Sciences, University of Molise, via F. De Sanctis snc, 86100 Campobasso, Italy.
Mariasilvia
M
D'Andrea
CBM S.c.r.l, SS 14 - km 163.5 AREA Science Park, 34149 Basovizza, TS Italy.
Danilo
D
Licastro
Department of Agricultural, Environmental and Food Sciences, University of Molise, via F. De Sanctis snc, 86100 Campobasso, Italy.
Fabio
F
Pilla
Institute of Zootechnics, Catholic University of the Sacred Heart, via Emilia Parmense 84, 29133 Piacenza, Italy.
Paolo
P
Ajmone-Marsan
Institute of Zootechnics, Catholic University of the Sacred Heart, via Emilia Parmense 84, 29133 Piacenza, Italy.
Andrea
A
Minuti
Department of Agriculture, Food, Environment and Animal Science (DI4A), University of Udine, via delle Scienze 206, 33100 Udine, Italy.
Sandy
S
Sgorlon
Acute phase proteins; Adaptive response; Dynamic impact approach (DIA); Hypothalamic-pituitary-adrenal (HPA) axis; RNA-Seq; Stress response; Transcriptomics