We also identified some oviparous-specific proteins (VTG1, VTG2, AVD, APOV1) (Fig

We also identified some oviparous-specific proteins (VTG1, VTG2, AVD, APOV1) (Fig. fluid proteome at day 11 of development, before egg white transfer. These proteins were essentially associated with the metabolism of nutrients, immune response and developmental processes. Forty-eight proteins were common to both chicken and human amniotic fluids, including serum albumin, apolipoprotein A1 and alpha-fetoprotein. We further investigated the effective role of chicken amniotic fluid in innate defense and revealed that it exhibits significant antibacterial activity at day 11 of development. This antibacterial potential is usually drastically enhanced after egg white transfer, presumably due to lysozyme, avian beta-defensin 11, vitelline membrane outer layer protein 1, and beta-microseminoprotein-like as the most likely antibacterial candidates. Interestingly, several proteins recovered in the chicken amniotic fluid prior and after egg white transfer are uniquely found in birds (ovalbumin and related proteins X and Y, avian beta-defensin 11) or oviparous species (vitellogenins 1 and 2, riboflavin-binding protein). This study provides an integrative overview of the chicken amniotic fluid proteome and opens stimulating perspectives in deciphering the role of avian egg-specific proteins in embryonic Val-cit-PAB-OH development, including innate immunity. These proteins may Val-cit-PAB-OH constitute Rabbit polyclonal to HER2.This gene encodes a member of the epidermal growth factor (EGF) receptor family of receptor tyrosine kinases.This protein has no ligand binding domain of its own and therefore cannot bind growth factors.However, it does bind tightly to other ligand-boun useful biomarkers for poultry production to detect hazardous situations (stress, contamination, etc.), that may negatively impact the development of the chicken embryo. strong class=”kwd-title” Keywords: Biofluids*, Developmental biology*, Mass Spectrometry, Multifunctional Val-cit-PAB-OH Proteins*, Omics, Physiology*, Protein Identification*, Microbiology, Animal biology, Comparative Val-cit-PAB-OH biology, Gene ontology analysis, Protein function In oviparous species, embryonic development depends on the various components, nutrients and structures composing the eggshell, the egg yolk, the egg white and the vitelline membrane (1). It also relies on the proper development of the extra-embryonic structures, namely the yolk sac, the amniotic sac and the allantoic/chorioallantoic sac (1) (Fig. 1 em A /em ,). These structures develop at the very early stages of development and originate from embryonic tissues but are not considered to be part of the embryonic body (2). They are discarded or resorbed at hatching. These living structures are partly preserved among amniote species, but exhibit evolutionary particularities depending Val-cit-PAB-OH on the embryonic development mode (3). The yolk sac, which appears in the first stages of development, degenerates rapidly in mammals (Fig. 1 em B /em ,), whereas in some birds, it participates in digestive processes until the last stages of incubation prior to complete abdominal resorption at hatch. The yolk sac may have many other functions, which are temporally regulated during incubation: it resembles the liver in the synthesis of plasma proteins, the bone marrow in erythropoiesis, and the intestine, in digestion of nutrients and their transport to the embryo (4). Thus, the yolk sac plays different roles to support or replace the functions of several organs that have not yet reached their full functional capacity. The chorioallantoic sac is composed of the chorioallantoic membrane, which results from the fusion of the chorion and the allantois at day 5/6 of incubation (ED5/ED6), and it includes the allantoic fluid. It is a highly vascularized structure that performs many functions during chicken embryonic development: it collects nitrogenous and excretory products from your embryonic metabolism, it participates in respiratory exchange, in calcium transport from your eggshell toward the embryo, in ion and water reabsorption from your allantoic fluid and, thus, in acid-base homeostasis (2, 5). In humans, the allantoic sac forms only a part of the umbilical cord. Concerning the amniotic sac, it is described in all amniotes as a structure, with amniotic fluid (AF)1, which protects the embryo against mechanical shocks, dehydration or adhesion to the other extra-embryonic membranes. It also serves as a source of nutrients (6). It provides a favorable environment for the development of the embryo: pH of about 7.1 to 7.3, stable temperature, and sensorial activation (taste, sense of smell and hearing) (7). Open in a separate windows Fig. 1. Schematic representation of the extraembryonic structures during the chicken ( em A /em ,) and human embryonic development ( em B /em ,); chicken embryo at mid-incubation (11 days) and human embryo at mid-gestation (21 weeks), respectively. Human AF is usually a fluctuating milieu mainly composed of water (about 96.4%), minerals, trace elements, carbohydrates, hormones, glucose, lipids, urea, cells, free amino-acids, proteins and peptides (6, 8). Its biochemical composition changes with gestational age/developmental stage as a result of various physiological mechanisms including feto-maternal exchanges: AF swallowing and lung fluid.