AUTHOR=Malila Yuwares , Uengwetwanit Tanaporn , Thanatsang Krittaporn V. , Arayamethakorn Sopacha , Srimarut Yanee , Petracci Massimiliano , Soglia Francesca , Rungrassamee Wanilada , Visessanguan Wonnop 

TITLE=Insights Into Transcriptome Profiles Associated With Wooden Breast Myopathy in Broilers Slaughtered at the Age of 6 or 7 Weeks

JOURNAL=Frontiers in Physiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2021.691194

DOI=10.3389/fphys.2021.691194

ISSN=1664-042X

ABSTRACT=<p>Transcriptomes associated with wooden breast (WB) were characterized in broilers at two different market ages. Breasts (<italic>Pectoralis major</italic>) were collected, 20-min postmortem, from male Ross 308 broilers slaughtered at 6 and 7 weeks of age. The breasts were classified as “non-WB” or “WB” based on palpation hardness scoring (non-WB = no abnormal hardness, WB = consistently hardened). Total RNA was isolated from 16 samples (<italic>n</italic> = 3 for 6 week non-WB, <italic>n</italic> = 3 for 6 week WB; <italic>n</italic> = 5 for 7 week non-WB, <italic>n</italic> = 5 for 7 week WB). Transcriptome was profiled using a chicken gene expression microarray with one-color hybridization technique, and compared between non-WB and WB samples of the same age. Among 6 week broilers, 910 transcripts were differentially expressed (DE) (false discovery rate, FDR &lt; 0.05). Pathway analysis underlined metabolisms of glucose and lipids along with gap junctions, tight junction, and focal adhesion (FA) signaling as the top enriched pathways. For the 7 week broilers, 1,195 transcripts were identified (FDR &lt; 0.05) with regulation of actin cytoskeleton, mitogen-activated protein kinase (MAPK) signaling, protein processing in endoplasmic reticulum and FA signaling highlighted as the enriched affected pathways. Absolute transcript levels of eight genes (actinin-1 – <italic>ACTN1</italic>, integrin-linked kinase – <italic>ILK</italic>, integrin subunit alpha 8 – <italic>ITGA8</italic>, integrin subunit beta 5 – <italic>ITGB5</italic>, protein tyrosine kinase 2 – <italic>PTK2</italic>, paxillin – <italic>PXN</italic>, talin 1 – <italic>TLN1</italic>, and vinculin – <italic>VCL</italic>) of FA signaling pathway were further elucidated using a droplet digital polymerase chain reaction. The results indicated that, in 6 week broilers, <italic>ITGA8</italic> abundance in WB was greater than that of non-WB samples (<italic>p</italic> &lt; 0.05). Concerning 7 week broilers, greater absolute levels of <italic>ACTN1</italic>, <italic>ILK</italic>, <italic>ITGA8</italic>, and <italic>TLN1</italic>, accompanied with a reduced <italic>ITGB5</italic> were found in WB compared with non-WB (<italic>p</italic> &lt; 0.05). Transcriptional modification of FA signaling underlined the potential of disrupted cell-cell communication that may incite aberrant molecular events in association with development of WB myopathy.</p>