Hydroxymethylation across the cattle brain
Conference Year
January 2021
Abstract
Epigenetic markers, such as 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC), are important factors that influence transcription and subsequently affect expression of economically important phenotypes. DNA methylation is a dynamic epigenetic marker that can be added and removed from DNA nucleotides. The removal pathway begins when 5-methylcytosine (5-mC) is oxidized to 5-hydroxymethylcytosine (5-hmC). Both 5-mC and 5-hmC are stable epigenetic markers that influence transcription where 5-mC is thought to inhibit transcription and 5-hmC is thought to promote transcription. Hydroxymethylation has recently been established as influential in the brain, but has not previously been studied in cattle. The goal of this work is to identify the presence of 5-hmC in four limbic system tissues of the bovine and examine the association between 5-hmC and docility, an economically important trait in cattle. To accomplish that goal, we utilized a combination of whole genome bisulfite sequencing (WGBS) and oxidative reduced representation bisulfite sequencing (oxRRBS) techniques to identify 5-hmC across the genome at a single nucleotide resolution. Four unique brain tissues (prefrontal cortex, periaqueductal gray, cingulate gyrus, hippocampus) were analyzed for two groups of steers with extreme measures of docility (n=4 per group). Our findings identify hydroxymethylation in each tissue and across the genome. However, 5-hmC varied across chromosomes in a tissue-specific manner. Additionally, differential 5-hmC was identified between docile and non-docile animals in three tissues. The amount of differential 5-hmC varied significantly between tissues, emphasizing the tissue-specific nature of 5-hmC within the brain. These data show the presence of 5-hmC in the bovine brain, which emphasizes the need to expand upon this work to differentiate between 5-hmC and 5-mC.
Primary Faculty Mentor Name
Dr. Stephanie McKay
Faculty/Staff Collaborators
Bonnie Cantrell, Brenda Murdoch, Rick Funston, Robert Weaber, Stephanie McKay
Status
Graduate
Student College
College of Agriculture and Life Sciences
Program/Major
Cellular, Molecular and Biomedical Sciences
Primary Research Category
Biological Sciences
Hydroxymethylation across the cattle brain
Epigenetic markers, such as 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC), are important factors that influence transcription and subsequently affect expression of economically important phenotypes. DNA methylation is a dynamic epigenetic marker that can be added and removed from DNA nucleotides. The removal pathway begins when 5-methylcytosine (5-mC) is oxidized to 5-hydroxymethylcytosine (5-hmC). Both 5-mC and 5-hmC are stable epigenetic markers that influence transcription where 5-mC is thought to inhibit transcription and 5-hmC is thought to promote transcription. Hydroxymethylation has recently been established as influential in the brain, but has not previously been studied in cattle. The goal of this work is to identify the presence of 5-hmC in four limbic system tissues of the bovine and examine the association between 5-hmC and docility, an economically important trait in cattle. To accomplish that goal, we utilized a combination of whole genome bisulfite sequencing (WGBS) and oxidative reduced representation bisulfite sequencing (oxRRBS) techniques to identify 5-hmC across the genome at a single nucleotide resolution. Four unique brain tissues (prefrontal cortex, periaqueductal gray, cingulate gyrus, hippocampus) were analyzed for two groups of steers with extreme measures of docility (n=4 per group). Our findings identify hydroxymethylation in each tissue and across the genome. However, 5-hmC varied across chromosomes in a tissue-specific manner. Additionally, differential 5-hmC was identified between docile and non-docile animals in three tissues. The amount of differential 5-hmC varied significantly between tissues, emphasizing the tissue-specific nature of 5-hmC within the brain. These data show the presence of 5-hmC in the bovine brain, which emphasizes the need to expand upon this work to differentiate between 5-hmC and 5-mC.