Temporal and spatial regulation of integrin vitronectin receptor mRNAs in the embryonic chick retina

Invest Ophthalmol Vis Sci. 1996 May;37(6):1084-96.


Purpose: To identify integrin vitronectin receptor subunit mRNAs in the developing avian retina and to track their expression.

Methods: Reverse transcription-polymerase chain reaction was used to identify integrin vitronectin receptor subunit mRNAs expressed in embryonic chick retina. cDNA clones encoding the beta 5 subunit were isolated and sequenced. Expression patterns of mRNAs encoding alpha v, beta 3, and beta 5 subunits were analyzed using northern analysis and in situ hybridization.

Results: Integrin beta 1, beta 3, and beta 5 subunit mRNA were identified in embryonic day 6 chick retina. The sequence of chicken beta 5 was 77% identical to that of human beta 5, and sequences with known signaling functions were highly conserved. Integrin alpha v, beta 3, and beta 5 mRNAs were expressed throughout the development of the embryonic retina, with the highest levels per retina observed around the embryonic day 9. In situ hybridization showed that both beta 3 and beta 5 were expressed throughout the developing retina, particularly in undifferentiated neuroepithelial precursor cells. At later times, beta 3 was expressed uniformly throughout the retina, whereas beta 5 expression was highest in a band throughout the central retina.

Conclusions: The strong conservation of sequences with known signaling functions in chicken beta 5 suggests that it functions in a manner similar to human beta 5. Spatial expression patterns of vitronectin receptor subunits at early times of development point to a range of possible functions beyond axon outgrowth, including retinoblast proliferation, adhesion, and migration.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Blotting, Northern
  • Chick Embryo
  • Chickens
  • Cloning, Molecular
  • DNA, Complementary / analysis
  • DNA, Complementary / isolation & purification
  • Gene Expression Regulation, Developmental*
  • Humans
  • In Situ Hybridization
  • Integrins / genetics
  • Integrins / metabolism
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • Receptors, Vitronectin / genetics
  • Receptors, Vitronectin / metabolism*
  • Retina / embryology*
  • Retina / metabolism*
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Transcription, Genetic
  • Vitronectin / genetics
  • Vitronectin / metabolism


  • DNA, Complementary
  • Integrins
  • RNA, Messenger
  • Receptors, Vitronectin
  • Vitronectin