Retinal accumulation of the phosducin/T beta gamma and transducin complexes in developing normal mice and in mice and dogs with inherited retinal degeneration.

Abstract

Rod photoreceptors of mammalian retinas contain a 33-kDa phosphoprotein, phosducin, which complexes with the beta, gamma-subunits of transducin (T beta gamma). The level of phosducin phosphorylation is modulated by light, suggesting that the phosducin/T beta gamma complex has a pivotal role in light-regulated events that occur in photoreceptors. We have investigated, in developing mouse retinas, the age at which the complex is first detected and the subsequent accumulation of the phosducin/T beta gamma complex during postnatal life. Western blot analysis detected immunoreactivity both for phosducin and T beta in retinal homogenates of 3-day-old mice. Thereafter, the level of immunoreactivity for both proteins increased steadily, to reach adult levels in the next 2 postnatal weeks. Gel filtration analysis of extracts from immature mouse retina showed that phosducin and T beta co-eluted, like the phosducin/T beta gamma complex of adult retina, as a 77-kDa complex, indicating that the phosducin/T beta gamma complex is formed when photoreceptors first synthesize the components of the complex. While the levels of the phosducin/T beta gamma complex increased steadily during the first 2 postnatal weeks, the subunits of transducin complex, T alpha together with additional amounts of T beta gamma, only started to appear around the 7-9th postnatal day, and the level of transducin complex increased sharply at 11-14 days to reach adult levels that are similar to those of phosducin/T beta gamma complex.(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: R H Lee, B S Lieberman, R N Lolley
• Journal: Experimental eye research (Exp Eye Res) Vol. 51 Issue 3 Pg. 325-33 (Sep 1990) ISSN: 0014-4835 [Print] England
• PMID: 2401349 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Eye Proteins
• GTP-Binding Protein Regulators
• Macromolecular Substances
• Phosphoproteins
• phosducin
• Transducin

Topics

• Animals
• Chromatography, High Pressure Liquid
• Dogs
• Eye Proteins (metabolism)
• GTP-Binding Protein Regulators
• Macromolecular Substances
• Mice
• Mice, Inbred BALB C
• Mice, Inbred C57BL
• Mice, Mutant Strains
• Phosphoproteins (metabolism)
• Reference Values
• Retina (growth & development, metabolism)
• Retinal Degeneration (genetics, metabolism)
• Transducin (metabolism)