Rat liver gap junction protein: properties and partial sequence.

B J Nicholson; M W Hunkapiller; L B Grim; L E Hood; J P Revel

doi:10.1073/pnas.78.12.7594

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Rat liver gap junction protein: properties and partial sequence.

B J Nicholson·M W Hunkapiller·L B Grim·L E Hood·J P Revel

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Abstract

Gap junctions, strongly implicated as channels for direct cell-to-cell communication, have been isolated from rat liver in high yield and purity. These gap junction fractions contain few morphologically recognizable contaminants, but NaDodSO4/polyacrylamide gel electrophoresis reveals a number of polypeptides. With the exception of a nonjunctional component of Mr 38,000 and some poorly soluble material, including collagen, all the polypeptides have very similar or identical two-dimensional peptide maps and arise from proteolytic cleavage of the COOH-terminus or aggregation of a Mr 28,000 protein. We report the sequence of the NH2-terminal 52 amino acids of this protein. The polypeptide (Mr approximately equal to 10,000) characteristic of trypsin-treated gap junction preparations is shown to be two distinct polypeptides, both derived from the Mr 28,000 protein.

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Amino Acid Sequence Animals Cell Communication Connexins Intercellular Junctions Liver Membrane Proteins Molecular Weight Peptide Fragments Protein Binding Rats Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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B J Nicholson, M W Hunkapiller, L B Grim, L E Hood, J P Revel. 1981. Rat liver gap junction protein: properties and partial sequence.. https://doi.org/10.1073/pnas.78.12.7594

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