Human netrin-G1 isoforms show evidence of differential expression.

Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Genomics (Impact Factor: 2.79). 08/2005; 86(1):112-6. DOI: 10.1016/j.ygeno.2005.04.004
Source: PubMed

ABSTRACT The recently identified netrins-G1 and -G2 form a distinct subgroup within the UNC-6/netrin gene family of axon guidance molecules. In this study, we determined the size and structure of the exon/intron layout of the human netrin-G1 (NTNG1) and -G2 (NTNG2) genes. Northern analysis of both genes showed limited nonneuronal but wide brain expression, particularly for NTNG2. Reverse transcriptase PCR detected nine alternatively spliced isoforms including four novel variants of NTNG1 from adult brain. A semiquantitative assay established that major expression was restricted to isoforms G1c, G1d, G1a, and G1e in the brain and to G1c in the kidney. There is also evidence of developmental regulation of these isoforms between fetal and adult brain. In conclusion, NTNG1 may use alternative splicing to diversify its function in a developmentally and tissue-specific manner.

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Available from: Shigeyoshi Itohara, Jul 15, 2015
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    • "interact with either netrinG1 or G2, but binds to the receptor protein tyrosine phosphatase LAR family of transmembrane proteins (Woo et al, 2009). NGL1 and NGL2 proteins as well as NetrinG1 and G2 exhibit complimentary patterns of expression in the developing and mature brain (Nakashiba et al, 2002; Meerabux et al, 2005). These observations raised the possibility that their differential expression and selective binding might form a molecular code contributing to the specificity of neuronal circuits. "
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    • "Northern blot analysis indicates that mouse netrin-G1 and netrin-G2 mRNAs are predominantly expressed in brain, with weak expression of netrin-G2 in other tissues including heart, lung, and kidney (Nakashiba et al., 2000; Nakashiba et al., 2002; Yin et al., 2002). Expression of splice variants of human netrin-G1 mRNAs is regulated in a development-and tissuedependent manner (Meerabux et al., 2005). In situ hybridization indicates that netrin-G1 and netrin-G2 mRNAs exhibit mainly nonoverlapping expression patterns in brain regions (Nakashiba et al., 2000, 2002; Yin et al., 2002). "
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    • "We also examined the relative expression of NTNG1 mRNA isoforms in human fetal and adult brain and confirmed previous findings that these isoforms are developmentally regulated (Meerabux et al, 2005). In both studies, G1d is the predominant isoform in fetal brain, whilst G1c is the most abundantly expressed isoform in adult brain; the expression of G1e mRNA is also reduced in adult as compared to fetal brain, whilst G1a mRNA expression increases during brain development. "
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