Changes in chicken egg white cystatin concentration and isoforms during embryogenesis.
1. A higher concentration of cystatin, measured using the ELISA technique, was found in whites from unfertilised than fertilised eggs. 2. Up to day 8 of embryogenesis a decrease in cystatin concentration was observed, then at d 10 the concentration rose reaching the maximal value at d 14. 3. Immunoblot analyses showed both phosphorylated and nonphosphorylated isoforms of chicken cystatin in unfertilised egg white as well as in egg yolk and chicken serum. 4. Significantly lower immunostaining of the phosphorylated form after the 4th d of embryogenesis in egg white suggests its preferential transport into the yolk sac.
Golab
K
K
Department of Pharmaceutical Biochemistry, Wroclaw University of Medicine, Poland. golab@bf.uni.wroc.pl
Gburek
J
J
Gawel
A
A
Warwas
M
M
D000367:Age Factors; D000818:Animals; D002642:Chick Embryo / Q000254:growth & development*; D015891:Cystatins / Q000032:analysis*; D015853:Cysteine Proteinase Inhibitors / Q000032:analysis*; D004529:Egg White; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D015151:Immunoblotting / Q000662:veterinary; D010063:Ovum / Q000737:chemistry*; D010766:Phosphorylation; D020033:Protein Isoforms; D015053:Zygote / Q000737:chemistry*
D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors; D020033:Protein Isoforms; C100158:cystatin, egg-white