Sps-3 transcript levels are determined by multiple remote sequence elements.
The region from 1.4 to 2.7 kb upstream of Drosophila melanogaster gene Sgs-3 is responsible for a 10-fold increase in Sgs-3 transcript levels in the third instar larval salivary gland. This region includes the related Sgs-7 gene from the 68C glue gene cluster as well as 400 bp of its 5' sequences. We show that two elements are involved, each contributing a modest 3-fold effect. One of these includes Sgs-7 transcribed sequences some 2.3 kb upstream of Sgs-3, although Sgs-7 transcription is not involved. Although important for the overall levels of Sgs-3 expression, they are clearly not strong, viral-like enhancer elements. We propose that many position effects observed in P element transformation studies are the consequence of insertion in the vicinity of similar elements dispersed throughout the genome and having modest effects on transcript levels.
Giangrande
A
A
Laboratoire de Génétique Moléculaire des Eucaryotes du CNRS, Unité 184 de Biologie Moléculaire et de Génie Génétique de l'INSERM, Faculté de Médecine, 11, rue Humann, 67085 Strasbourg Cédex, France.
Mettling
C
C
Richards
G
G
D000818:Animals; D004331:Drosophila melanogaster / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D005967:Glue Proteins, Drosophila / Q000096:biosynthesis / Q000235:genetics*; D005810:Multigene Family; D014158:Transcription, Genetic
D005967:Glue Proteins, Drosophila; C424365:Sgs3 protein, Drosophila