A comparison of the bovine uterine and plasma proteome using iTRAQ proteomics

Abstract

Early embryo loss is a key factor affecting fertility in dairy and beef herds. Prior to implantation, the bovine embryo spends around 16 days free-floating in the uterine environment and is dependent on the composition of uterine fluid for normal growth and development. However, there is a lack of information regarding the protein composition of the bovine uterus and how it relates to plasma. In this study, uterine flushings (UF) (n = 6) and blood plasma (n = 4) were collected from beef heifers on day 7 of the oestrous cycle, albumin depleted and compared using iTRAQ proteomics. A total of 35 proteins were higher and 18 were lower in UF including metabolic enzymes, proteins with anti-oxidant activity and those involved in modulation of the immune response. This study confirms the dynamic nature of the bovine uterine proteome and that it differs from plasma. Factors affecting the uterine proteome and how it impacts on embryo survival warrant further study.

Mouse early extra-embryonic lineages activate compensatory endocytosis in response to poor maternal nutrition

“…Embryos from chow-fed mothers were cultured from the two-cell stage [embryonic day (E) 1.5] to blastocyst stage (E3.5) in KSOM medium containing either 1 or 4 mg/ml bovine serum albumin (BSA) concentration before evaluating TE endocytosis activity using the fluid marker fluorescein isothiocyanate (FITC)-dextran in the same medium. BSA was chosen because albumin is the major protein found within uterine fluid (Velazquez et al, 2010;Faulkner et al, 2012). We found both the number and collective volume of FITC-dextran labelled vesicles within blastocyst TE to be increased after culture in 1 mg/ml BSA ( Fig.…”

Proteomic analysis of uterine fluid during the pre-implantation period of pregnancy in cattle

“…Some recent studies have described the protein content of ULF in cyclic heifers (Mullen et al 2012a(Mullen et al , 2012b, at a single timepoint either considerably before (day 7: Faulkner et al 2012) or after (day 18: Ledgard et al 2009) pregnancy recognition, or in non-physiological models involving the transfer of up to 50 embryos per recipient (day 7: Munoz et al 2012). This study provides new knowledge regarding the composition and quantitative changes in ULF during key morphological events in early pregnancy in cattle.…”

Plasma-based proteomics reveals immune response, complement and coagulation cascades pathway shifts in heat-stressed lactating dairy cows

“…Several studies reported plasma proteomics profiles in dairy cows determined by iTRAQ analysis [7,8]. To date, however, there were few proteomics studies aimed at investigating the effects of HS on the plasma proteomics in lactating dairy cows.…”