Mutation Detection in the   and   Alleles of the Sodium Channel

Kohrman, David C.; Harris, John B.; Meisler, Miriam H.

doi:10.1074/jbc.271.29.17576

Cited by 135 publications

(99 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using PCR and capillary sequencing, we validated 11 de novo L1 insertions (Table 1; Supplemental Table 2). All 11 were T F subfamily elements, consistent with previous reports of disease-causing L1 insertions in mice wherein all insertions for which sufficient L1 sequence was present for subfamily distinction were identified as T F elements (Kingsmore et al 1994;Mulhardt et al 1994;Kohrman et al 1996;Takahara et al 1996;Perou et al 1997;Naas et al 1998;Yajima et al 1999;Cunliffe et al 2001). De novo L1 insertions bore hallmarks of L1 retrotransposition by target-primed reverse transcription (TPRT), including insertion at sequences resembling the L1 endonuclease cleavage motif (5 ′ -TTTT/AA-3 ′ ), the presence of 13-to 17-bp target-site duplications (TSDs), and 3 ′ poly(A) tracts (Table 1; Supplemental Figs.…”

Section: Resultssupporting

confidence: 77%

Heritable L1 retrotransposition in the mouse primordial germline and early embryo

et al. 2017

View full text Add to dashboard Cite

LINE-1 (L1) retrotransposons are a noted source of genetic diversity and disease in mammals. To expand its genomic footprint, L1 must mobilize in cells that will contribute their genetic material to subsequent generations. Heritable L1 insertions may therefore arise in germ cells and in pluripotent embryonic cells, prior to germline specification, yet the frequency and predominant developmental timing of such events remain unclear. Here, we applied mouse retrotransposon capture sequencing (mRC-seq) and whole-genome sequencing (WGS) to pedigrees of C57BL/6J animals, and uncovered an L1 insertion rate of ≥1 event per eight births. We traced heritable L1 insertions to pluripotent embryonic cells and, strikingly, to early primordial germ cells (PGCs). New L1 insertions bore structural hallmarks of target-site primed reverse transcription (TPRT) and mobilized efficiently in a cultured cell retrotransposition assay. Together, our results highlight the rate and evolutionary impact of heritable L1 retrotransposition and reveal retrotransposition-mediated genomic diversification as a fundamental property of pluripotent embryonic cells in vivo.

show abstract

Section: Resultssupporting

confidence: 77%

Heritable L1 retrotransposition in the mouse primordial germline and early embryo

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Several mutant alleles of Scn8a have been characterized, showing various combinations of ataxia, dystonia, and muscle weakness [129][130][131]. Various deficits in Purkinje cell function have been found in Scn8a mutant mice, although no major loss of Purkinje cells, as reported in many other types of mutant mice, has been described except in older Scn8amedJo mice.…”

Section: Models Of Hereditary Ataxiasmentioning

confidence: 99%

Animal Models of Human Cerebellar Ataxias: a Cornerstone for the Therapies of the Twenty-First Century

Manto

Marmolino

2009

Cerebellum

View full text Add to dashboard Cite

Cerebellar ataxias represent a group of disabling neurological disorders. Our understanding of the pathogenesis of cerebellar ataxias is continuously expanding. A considerable number of laboratory animals with neurological mutations have been reported and numerous relevant animal models mimicking the phenotype of cerebellar ataxias are becoming available. These models greatly help dissecting the numerous mechanisms of cerebellar dysfunction, a major step for the assessment of therapeutics targeting a given deleterious pathway and for the screening of old or newly synthesized chemical compounds. Nevertheless, differences between animal models and human disorders should not be overlooked and difficulties in terms of characterization should not be occulted. The identification of the mutations of many hereditary ataxias, the development of valuable animal models, and the recent identifications of the molecular mechanisms underlying cerebellar disorders represent a combination of key factors for the development of anti-ataxic innovative therapies. It is anticipated that the twenty-first century will be the century of effective therapies in the field of cerebellar ataxias. The animal models are a cornerstone to reach this goal.

show abstract

“…Correctly spliced Scn8a transcripts were specifically amplified with a forward primer in exon 1 (59-CCG ACA GTT TCA AGC CTT TCA CCC-39) and a reverse primer in exon 2 (59-AGG ACT TAG AAT GTA CAA GGC AGG-39). Only correctly spliced Scn8a transcripts are amplified with these primers as the exon 3 splicesite mutation in Scn8a medJ results in a majority of incorrectly spliced transcripts lacking exon 2 and exon 3 (Kohrman et al 1996). RT-PCR products were examined on agarose gels.…”

Section: Methodsmentioning

confidence: 99%

“…A direct role for SCNM1 in splicing the Scn8a medJ transcript was subsequently demonstrated in a cell culture assay (Howell et al 2007). The Scn8a medJ mutation is a 4-bp deletion in the splice donor site of exon 3, nucleotides 15 to 18, generating a weak site with a C nucleotide at the consensus 15G position (Kohrman et al 1996). In the presence of a wild-type Scnm1 gene, only 10% of the Scn8a medJ transcripts are correctly spliced and encode an active channel, while $90% of the transcripts skip exon 2 and exon 3.…”

mentioning

confidence: 99%

A Targeted Deleterious Allele of the Splicing Factor SCNM1 in the Mouse

et al. 2008

View full text Add to dashboard Cite

The auxiliary spliceosomal protein SCNM1 contributes to recognition of nonconsensus splice donor sites. SCNM1 was first identified as a modifier of the severity of a sodium channelopathy in the mouse. The most severely affected strain, C57BL/6J, carries the variant allele SCNM1 R187X, which is defective in splicing the mutated donor site in the Scn8a medJ transcript. To further probe the in vivo function of SCNM1, we constructed a floxed allele and generated a mouse with constitutive deletion of exons 3-5. The SCNM1 D3-5 protein is produced and correctly localized to the nucleus, but is more functionally impaired than the C57BL/6J allele. Deficiency of SCNM1 did not significantly alter other brain transcripts. We characterized an ENU-induced allele of Scnm1 and evaluated the ability of wild-type SCNM1 to rescue lethal mutations of I-mfa and Brunol4. The phenotypes of the Scnm1 D3-5 mutant confirm the role of this splice factor in processing the Scn8a medJ transcript and provide a new allele of greater severity for future studies. SODIUM channel modifier 1 (Scnm1) is an auxiliary splice factor that was identified by its role in the strain-specific lethality of the sodium channel mutation Scn8a medJ (Buchner et al. 2003). A direct role for SCNM1 in splicing the Scn8a medJ transcript was subsequently demonstrated in a cell culture assay (Howell et al. 2007). The Scn8a medJ mutation is a 4-bp deletion in the splice donor site of exon 3, nucleotides 15 to 18, generating a weak site with a C nucleotide at the consensus 15G position (Kohrman et al. 1996). In the presence of a wild-type Scnm1 gene, only 10% of the Scn8a medJ transcripts are correctly spliced and encode an active channel, while $90% of the transcripts skip exon 2 and exon 3. In the presence of the C57BL/6J-specific Scnm1 R187X allele, the amount of full-length transcript is reduced to 5% and the Scn8a medJ mice do not survive (Buchner et al. 2003). It is not clear from the earlier studies whether Scnm1 R187X is a null allele or retains partial function.SCNM1 is a 229-amino-acid protein with a bipartite nuclear localization signal near the N terminus and one C2H2 zinc finger of the U1C type ( Figure 1A). It is an accessory component of the U1 splicesome protein complex and interacts with the spliceosomal Sm and U1-70K proteins (Howell et al. 2007). Along with other members of the U1C protein family, SCNM1 is thought to contribute to the recognition of different subsets of nonconsensus splice donor sites (Roca et al. 2005). By analogy with the effect of Scnm1 R187X on the splicing of Scn8a medJ

show abstract

Mutation Detection in the and Alleles of the Sodium Channel

Cited by 135 publications

References 41 publications

Heritable L1 retrotransposition in the mouse primordial germline and early embryo

Heritable L1 retrotransposition in the mouse primordial germline and early embryo

Animal Models of Human Cerebellar Ataxias: a Cornerstone for the Therapies of the Twenty-First Century

A Targeted Deleterious Allele of the Splicing Factor SCNM1 in the Mouse

Contact Info

Product

Resources

About