Primordial germ cell migration in the chick and mouse embryo: the role of the chemokine SDF-1/CXCL12.
As in many other animals, the primordial germ cells (PGCs) in avian and reptile embryos are specified in positions distinct from the positions where they differentiate into sperm and egg. Unlike in other organism however, in these embryos, the PGCs use the vascular system as a vehicle to transport them to the region of the gonad where they exit the blood vessels and reach their target. To determine the molecular mechanisms governing PGC migration in these species, we have investigated the role of the chemokine stromal cell-derived factor-1 (SDF-1/CXCL12) in guiding the cells towards their target in the chick embryo. We show that sdf-1 mRNA is expressed in locations where PGCs are found and towards which they migrate at the time they leave the blood vessels. Ectopically expressed chicken SDF-1alpha led to accumulation of PGCs at those positions. This analysis, as well as analysis of gene expression and PGC behavior in the mouse embryo, suggest that in both organisms, SDF-1 functions during the second phase of PGC migration, and not at earlier phases. These findings suggest that SDF-1 is required for the PGCs to execute the final migration steps as they transmigrate through the blood vessel endothelium of the chick or the gut epithelium of the mouse.
Germ Cell Development, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany.
Jürg
J
Stebler
Derek
D
Spieler
Krasimir
K
Slanchev
Kathleen A
KA
Molyneaux
Ulrike
U
Richter
Vlad
V
Cojocaru
Victor
V
Tarabykin
Chris
C
Wylie
Michael
M
Kessel
Erez
E
Raz
D000595:Amino Acid Sequence; D000818:Animals; D001808:Blood Vessels / Q000166:cytology / Q000196:embryology; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000502:physiology*; D002642:Chick Embryo; D003001:Cloning, Molecular; D004064:Digestive System / Q000166:cytology / Q000196:embryology; D004627:Embryonic Induction / Q000235:genetics; D004847:Epithelial Cells / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D010053:Ovary / Q000166:cytology / Q000196:embryology; D010063:Ovum / Q000166:cytology* / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D013094:Spermatozoa / Q000166:cytology* / Q000502:physiology; D013737:Testis / Q000166:cytology / Q000196:embryology
D054377:Chemokine CXCL12; D019743:Chemokines, CXC; C515256:Cxcl12 protein, mouse