Intron retention

Intron retention results in the production of mRNAs and their encoded proteins of different lengths. Intron retention is commonly found in plants and lower multicellular organisms. 

Pampori, N.A. and B.H. Shapiro (2000). Nominal growth hormone pulses in otherwise normal masculine plasma profiles induce intron retention of overexpressed hepatic CYP2C11 with associated nuclear splicing deficiency. Endocrinology 141, 4100-4106. 

M. L Gysling, K. Intron retention as an alternative splice variant of the rat urocortin 1 gene. Neuroscience 2006, 140, 1245-1252. 

L gene was identified in PK Kowloon, Nepalese nonidentical twin girls who have been transfusion dependent (K9). The +1 position of intron 7 was replaced from QT to XT, resulting in retention of intron 7 in the R-PK mRNA. Consequently, the... 

V8. Vasconcelos, O., Sivakumar, K., Dalakas, M. C., Quezado, M., Nagle, J., Leon-Monzon, M., Dubnick, M., Gajdusek, C., and Goldfarb, L. G., Nonsense mutation in the phosphofructokinase muscle subunit gene associated with retention of intron 10 in one of the isolated transcripts in Ashkenzai Jewish patients with Tarui disease. Proc. Natl Acad. Sci. U.S.A. 92, 10322-10326 (1995). 

Moreover, COX-2 expression seems to be regulated by synaptic activity [36]. Recently, COX-3 was characterized as generated from COX-1 intron-1 retention [37]. COX-3 is expressed in brain [37], brain microvasculature [38] and has been proposed to be a target of the analgesic/ antipyretic acetaminophen [37,39]. 

Flowers J. M., Powell J. F., Leigh P. N., Andersen P., and Shaw C. E. (2001). Intron 7 retention and exon 9 skipping EAAT2 mRNA variants are not associated with amyotrophic lateral sclerosis. Ann. Neurol. 49 643-649. 

Qin N, Zhang SP, Reitz TL, et al. Cloning, expression, and functional characterization of human COX-1 splicing variants evidence for intron-1 retention. J Pharmacol Exp Ther 2005 315 1298-1305. 

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