Primary structure of mouse and rat nephrin cDNA and structure and expression of the mouse gene.
Nephrin is a central component of the glomerular podocyte slit diaphragm and is essential for the normal renal filtration process. This study describes the complete structure of the mouse nephrin gene, which was shown to be homologous to the human gene, the major difference being 30 exons in the mouse gene as opposed to 29 in human. The complete primary structure of mouse and rat nephrins was also determined. The sequence identity between the mouse and rat proteins was shown to be 93%, while both rodent proteins have only about 83% sequence identity with human nephrin. The availability of the three mammalian sequences is significant for the interpretation of sequence variants and mutations in the nephrin gene in patients with congenital nephrotic syndrome. In situ hybridization analyses of whole mouse embryos and tissues revealed high expression of nephrin in kidney glomeruli and, surprisingly, an intense and highly restricted expression in a set of cells in hindbrain and spinal cord. No expression was observed elsewhere. This expression pattern may explain occasionally occurring neural symptoms caused by inactivating mutations in the nephrin gene in patients with congenital nephrotic syndrome.
Putaala
Heli
H
Division of Matrix Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden.
Sainio
Kirsi
K
Developmental Biology Research Program, Institute of Biotechnology, University of Helsinki, Finland.
Sariola
Hannu
H
Developmental Biology Research Program, Institute of Biotechnology, University of Helsinki, Finland.
Tryggvason
Karl
K
Division of Matrix Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden.
D000818:Animals; D003001:Cloning, Molecular; D003062:Codon; D018076:DNA, Complementary / Q000235:genetics* / Q000302:isolation & purification; D005784:Gene Amplification; D015870:Gene Expression; D006801:Humans; D007672:Kidney Cortex / Q000378:metabolism; D008565:Membrane Proteins; D051379:Mice; D015336:Molecular Probe Techniques; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics*; D051381:Rats; D017422:Sequence Analysis, DNA
D003062:Codon; D018076:DNA, Complementary; D008565:Membrane Proteins; D011506:Proteins; C113267:nephrin