PT  - JOURNAL ARTICLE
AU  - Mongelard, Fabien
AU  - Labrador, Mariano
AU  - Baxter, Ellen M.
AU  - Gerasimova, Tatiana I.
AU  - Corces, Victor G.
TI  - <em>Trans</em>-splicing as a Novel Mechanism to Explain Interallelic Complementation in Drosophila
DP  - 2002 Apr 01
TA  - Genetics
PG  - 1481--1487
VI  - 160
IP  - 4
4099  - http://www.genetics.org/content/160/4/1481.short
4100  - http://www.genetics.org/content/160/4/1481.full
SO  - Genetics2002 Apr 01; 160
AB  - Two mutant alleles of the same gene, each located in one of the two homologous chromosomes, may in some instances restore the wild-type function of the gene. This is the case with certain combinations of mutant alleles in the mod(mdg4) gene. This gene encodes several different proteins, including Mod(mdg4)2.2, a component of the gypsy insulator. This protein is encoded by two separate transcription units that can be combined in a trans-splicing reaction to form the mature Mod(mdg4)2.2-encoding RNA. Molecular characterization of complementing alleles shows that they affect the two different transcription units. Flies homozygous for each allele are missing the Mod(mdg4)2.2 protein, whereas wild-type trans-heterozygotes are able to synthesize almost normal levels of the Mod(mdg4)2.2 product. This protein is functional as judged by its ability to form a functional insulator complex. The results suggest that the interallelic complementation in the mod(mdg4) gene is a consequence of trans-splicing between two different mutant transcripts. A conclusion from this observation is that the trans-splicing reaction that takes place between transcripts produced on two different mutant chromosomes ensures wild-type levels of functional protein.