FcRY is a key molecule controlling maternal blood IgY transfer to yolks during egg development in avian species.

Maternal immunoglobulin transfer plays a key role in conferring passive immunity to neonates. Maternal blood immunoglobulin Y (IgY) in avian species is transported to newly-hatched chicks in two steps: 1) IgY is transported from the maternal circulation to the yolk of maturing oocytes, 2) the IgY deposited in yolk is transported to the circulation of the embryo via the yolk sac membrane. An IgY-Fc receptor, FcRY, is involved in the second step, but the mechanism of the first step is still unclear.

Graphene oxide-dependent growth and self-aggregation into a hydrogel complex of exoelectrogenic bacteria.

Graphene oxide (GO) is reduced by certain exoelectrogenic bacteria, but its effects on bacterial growth and metabolism are a controversial issue. This study aimed to determine whether GO functions as the terminal electron acceptor to allow specific growth of and electricity production by exoelectrogenic bacteria. Cultivation of environmental samples with GO and acetate as the sole substrate could specifically enrich exoelectrogenic bacteria with Geobacter species predominating (51-68% of the total populations).

Amino acid substitution in the Cυ3 domain causes either elevation or reduction of IgY uptake into egg yolks of quail.

Egg yolks of avian species contain large quantities of immunoglobulin (Ig) Ys transferred from maternal blood circulation. However, it is unclear how maternal IgYs are incorporated into the egg yolks of maturing oocytes. The aim of this study was to identify the amino acid residues required for efficient IgY transport into the egg yolks of quail by utilizing recombinant quail IgY-Fc (qIgY-Fc).

Avian IgY is selectively incorporated into the egg yolks of oocytes by discriminating Fc amino acid residues located on the Cυ3/Cυ4 interface.

In avian species, maternal IgY is selectively incorporated into the egg yolks of maturing oocytes, but the relevance of receptor-mediated uptake is unclear. Here we investigated the critical amino acid residues of IgY required for egg yolk transport by conducting mutational analyses of selected residues located along the Cυ3 and Cυ4 domains of chicken IgY. Recombinant wild-type IgY-Fc (WT) and its mutants were synthesized, and their uptakes into the egg yolks of quail were determined.