Biochemistry and regulation of pre-mRNA splicing

Adams, Melissa D.; Rudner, David Z.; Rio, Donald C.

doi:10.1016/s0955-0674(96)80006-8

Cited by 129 publications

(90 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…18,20 On the basis of these various findings, it has been proposed that the choice between intronic and exonic splice sites may be regulated by changes in the relative level of expression of SR proteins and hnRNPs 18,20 with additional specificity being achieved if particular combinations of these antagonistic factors act preferentially on certain pre-mRNA transcripts. 16,17,20,21 Although this model is attractive in its simplicity, in the present study Western blot analysis failed to demonstrate substantial differences in the levels of these two families of splicing factors in T24 and PC3 cells, suggesting that more complex mechanisms operate to determine splice site selection in the context of CD44. Of course, it is quite possible that the functional activity of SR proteins and hnRNPs may differ in the two cell lines and studies are currently underway to determine whether these molecules are differentially phosphorylated or otherwise modified in a cell-specific manner.…”

Section: Discussioncontrasting

confidence: 58%

“…Attention in this regard has focused on members of a conserved family of ubiquitous and highly expressed RNA-binding proteins known as the SR proteins, so called because of the presence of a characteristic serine-argine-rich carboxy-terminal domain of variable length. 16,17 SR proteins function as an essential component of the constitutive splicing machinery playing a critical role in the early stages of spliceosome assembly. Importantly, they also seem to affect the alternative splicing of many different pre-mRNA transcripts, acting in a concentration-dependent manner and combinatorial pattern to promote the use of proximal alternative 5 0 splice sites.…”

Section: Discussionmentioning

confidence: 99%

“…Importantly, they also seem to affect the alternative splicing of many different pre-mRNA transcripts, acting in a concentration-dependent manner and combinatorial pattern to promote the use of proximal alternative 5 0 splice sites. 16,17 A number of SR protein antagonists have also been identified. These include hnRNP A1 18 and other hnRNP A/B family members (hnRNP A1B, A2 and B1).…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Molecular mechanisms regulating the tumor-targeting potential of splice-activated gene expression

Hayes

Dougherty

Davis³

et al. 2004

Cancer Gene Ther

View full text Add to dashboard Cite

Previous studies have suggested that differences in the ability of normal and malignant cells to process certain alternatively spliced pre-mRNA transcripts can be exploited as a potentially powerful means of targeting the expression of therapeutic genes to tumor cells in vivo and in vitro. Specifically, it was shown that efficient processing of minigene constructs containing the alternatively spliced CD44 exons v9 and v10 only occurs in tumor cells that express CD44 isoforms that incorporate these exons (e.g. CD44R1). In the present study, efforts were made to define the molecular mechanisms that underlie the apparent specificity of this process. RT-PCR analysis and DNA sequencing were used to characterize the various splicing events that occur between CD44 exons v8, v9 and v10 following transfection of minigene constructs containing these various exons into CD44R1-positive (PC3) and CD44R1-negative (T24) cell lines. The results obtained confirm that although the v8-v9 intron is efficiently removed in both CD44R1-positive and CD44R1-negative cells, the corresponding v9-v10 intron is accurately spliced and the exons appropriately joined only in lines that express v10-containing CD44 isoforms (e.g. PC3). In CD44R1-negative cell lines (e.g. T24) alternative 5 0 and 3 0 splice sites located within the v9-v10 intron are preferentially used, resulting in various portions of the intron being retained within the final processed mRNA product. It is proposed that identification of these functionally important intronic sequence elements will facilitate the development of second generation ''splice activated gene expression'' vectors that may prove useful in various cancer gene therapy applications.

show abstract

Section: Discussioncontrasting

confidence: 58%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Molecular mechanisms regulating the tumor-targeting potential of splice-activated gene expression

Hayes

Dougherty

Davis³

et al. 2004

Cancer Gene Ther

View full text Add to dashboard Cite

show abstract

“…Alternative splicing of mRNA regulates the production of a number of important biological molecules. Splice-editing of mRNA can regulate gene expression by preventing or promoting translation, or it can produce alternative protein products with disparate functions (Adams et al, 1996). From the number of genes that are now known to be regulated by alternative splicing, it is clear that splicing regulation is an important adjunct to promoter-mediated regulation of gene expression (Rubinfeld et al, 1997;Roberts et al, 1996).…”

Section: Discussionmentioning

confidence: 99%

TSG101 is not mutated in lung cancer but a shortened transcript is frequently expressed in small cell lung cancer

Proctor

Fan

et al. 1998

Oncogene

View full text Add to dashboard Cite

TSG101 is a candidate tumor suppressor gene whose deletion in NIH3T3 cells leads to spontaneous lung metastases in nude mice. Aberrant transcripts of TSG101 have been identi®ed in 47% of primary breast carcinomas, without evidence of intragenic deletions at the TSG101 locus on 11p15. To investigate the possible role of TSG101 in lung cancer, which often shows 11p allele loss, we performed transcript analysis and mutational analysis of TSG101 in lung cancer cell lines. Reverse transcriptase RT ± PCR and Northern analysis detected a common TSG101 transcript, shortened because of an internal deletion, which was expressed simultaneously with the wild-type transcript in 89% of small cell lung cancer (SCLC) lines. In contrast, the wild-type transcript was expressed alone in normal tissues, primary non-small cell lung cancer (NSCLC) specimens, and the majority of NSCLC cell lines. Sequence of the shortened SCLC transcript was identical to that of the most common aberrant transcript identi®ed in breast cancer, consisting of a deletion of exons 2 ± 4 and part of 1 and 5. Southern analysis of SCLC lines expressing the shortened transcript did not detect any intragenic deletions. Single strand conformational polymorphism (SSCP) analysis and direct sequencing of TSG101 cDNAs also identi®ed no mutations or deletions. These results suggest that TSG101 is not mutated in lung cancer but that aberrant splicing of TSG101 occurs in SCLC.

show abstract

“…One possibility is that the new acceptor site is inherently more efficient than the natural acceptor, but the natural acceptor's proximity to the branch site makes it the preferred location for splicing. The first AG downstream of an intron's branch site is normally selected for exon ligation 36 . Thus, mutation of the native acceptor AG would allow splicing to occur at the next AG downstream, whose context may be better suited for efficient splicing.…”

Section: Discussionmentioning

confidence: 99%

Adaptive Evolution of a Tagged Chimeric Gammaretrovirus: Identification of Novel cis-Acting Elements that Modulate Splicing

Logg

Baranick

Lemp

et al. 2007

Journal of Molecular Biology

View full text Add to dashboard Cite

SummaryRetroviruses are well known for their ability to incorporate envelope proteins from other retroviral strains and genera and even from other virus families. This characteristic has been widely exploited for the generation of replication-defective retroviral vectors, including those derived from murine leukemia virus (MLV), bearing heterologous envelope proteins. We desired to investigate the possibility of "genetically" pseudotyping replication-competent MLV by replacing the native env gene in a full-length viral genome with that of another gammaretrovirus. We previously developed replication-competent versions of MLV that stably transmit and express transgenes inserted in the 3′ untranslated region of the viral genome. In one such tagged MLV expressing green fluorescent protein, we replaced the native env sequence with that of gibbon ape leukemia virus (GALV). Although the GALV Env protein is commonly used to make high titer pseudotypes of MLV vectors, we found that the env replacement greatly attenuated viral replication. However, passage of cells exposed to the chimeric virus resulted in selection of mutants exhibiting rapid replication kinetics and different variants arose in different infections. Two of these variants had acquired mutations at or adjacent to the splice acceptor site and three others had acquired dual mutations within the long terminal repeat. Analysis of the levels of unspliced and spliced viral RNA produced by the parental and adapted viruses showed that the mutations gained by each of these variants functioned to reverse an imbalance in splicing caused by the env gene substitution. Our results reveal the presence of previously unknown cis-acting sequences in MLV that modulate splicing of the viral transcript and demonstrate that tagging of the retroviral genome with an easily assayed transgene can be combined with in vitro evolution to efficiently generate and screen for replicating mutants of replicationimpaired recombinant viruses.

show abstract

Biochemistry and regulation of pre-mRNA splicing

Cited by 129 publications

References 75 publications

Molecular mechanisms regulating the tumor-targeting potential of splice-activated gene expression

Molecular mechanisms regulating the tumor-targeting potential of splice-activated gene expression

TSG101 is not mutated in lung cancer but a shortened transcript is frequently expressed in small cell lung cancer

Adaptive Evolution of a Tagged Chimeric Gammaretrovirus: Identification of Novel cis-Acting Elements that Modulate Splicing

Contact Info

Product

Resources

About