Multiple connexins contribute to intercellular communication in the Xenopus embryo.
To explore the role of gap junctional intercellular communication (GJIC) during Xenopus embryogenesis, we utilized the host-transfer and antisense techniques to specifically deplete Cx38, the only known maternally expressed connexin. Cx38-depleted embryos developed normally but displayed robust GJIC between blastomeres at 32-128 cell stages, suggesting the existence of other maternal connexins. Analysis of embryonic cDNA revealed maternal expression of two novel connexins, Cx31 and Cx43.4, and a third, Cx43, that had been previously identified as a product of zygotic transcription. Thus, the early Xenopus embryo contains at least four maternal connexins. Unlike Cx38, expression of Cx31, Cx43 and Cx43.4 continue zygotically. Of these, Cx43.4 is the most abundant, accumulating significantly in neural structures including the brain, the eyes and the spinal cord.
Landesman
Yosef
Y
Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
Postma
Friso R
FR
Goodenough
Daniel A
DA
Paul
David L
DL
D000818:Animals; D036703:Blastula / Q000166:cytology / Q000378:metabolism*; D002450:Cell Communication / Q000235:genetics*; D002490:Central Nervous System / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism; D017630:Connexins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000032:analysis / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D019143:Evolution, Molecular; D005260:Female; D017629:Gap Junctions / Q000378:metabolism* / Q000648:ultrastructure; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014981:Xenopus / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D015053:Zygote / Q000166:cytology / Q000378:metabolism
D018031:Connexin 43; D017630:Connexins; D018076:DNA, Complementary; D016376:Oligonucleotides, Antisense; C082920:connexin 45; C102630:connexin 38; C068044:GJB3 protein, human