Abstract |
Distinct germline mutations in the gene (GJB3) encoding connexin 31 (Cx31) underlie the skin disease erythrokeratoderma variabilis (EKV) or sensorineural hearing loss with/without peripheral neuropathy. Here we describe a number of functional analyses to investigate the effect of these different disease-associated Cx31 mutants on connexon trafficking and intercellular communication. Immunostaining of a biopsy taken from an EKV patient harbouring the R42P mutation revealed sparse epidermal staining of Cx31, and, when present, it had a perinuclear localization. Transfection and microinjection studies in both keratinocytes and fibroblast cell lines also demonstrated that R42P and four other EKV-associated mutant Cx31 proteins displayed defective trafficking to the plasma membrane. The deafness/neuropathy only mutant 66delD had primarily a cytoplasmic localization, but some protein was visualized at the plasma membrane in a few transfected cells. Both 66delD- and R32W-Cx31/EGFP proteins had significantly impaired dye transfer rates compared to wild-type Cx31/ EGFP protein. A striking characteristic feature observed with the dominant skin disease Cx31 mutations was a high incidence of cell death. This was not observed with wild-type, R32W 66delD Cx31 proteins. In conclusion, we have identified some key cellular phenotypic differences with respect to disease-associated Cx31 mutations.
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Authors | Wei-Li Di, James Monypenny, John E A Common, Cameron T C Kennedy, Katalin A Holland, Irene M Leigh, Elizabeth L Rugg, Daniel Zicha, David P Kelsell |
Journal | Human molecular genetics
(Hum Mol Genet)
Vol. 11
Issue 17
Pg. 2005-14
(Aug 15 2002)
ISSN: 0964-6906 [Print] England |
PMID | 12165562
(Publication Type: Journal Article)
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Chemical References |
- Connexins
- DNA Primers
- Luminescent Proteins
- Recombinant Fusion Proteins
- GJB3 protein, human
- Green Fluorescent Proteins
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Topics |
- Biopsy
- Cell Communication
(physiology)
- Cell Death
(physiology)
- Cell Membrane
- Connexins
(genetics, metabolism)
- DNA Primers
(chemistry)
- Fibroblasts
(metabolism, pathology)
- Green Fluorescent Proteins
- Humans
- Keratinocytes
(metabolism, pathology)
- Keratosis
(genetics, metabolism, pathology)
- Luminescent Proteins
(genetics, metabolism)
- Microscopy, Confocal
- Microscopy, Fluorescence
- Mutagenesis, Site-Directed
- Peripheral Nervous System Diseases
(genetics, metabolism)
- Recombinant Fusion Proteins
(metabolism)
- Transfection
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