Glass Insulators

About the internal structure of glass insulators hundreds of nucleotides Yes, it is usually located in the Far promoter regulatory elements (enhancers) or negative regulatory factors (as heterochromatin) between one regulatory sequence. Gene expression insulator itself neither positive effect, there is no negative effect, its role is not to the role of other regulatory elements to effect activation or inactivation effect genes occur. The role of the insulator is directional, which is found in Drosophila experiments. Drosophila (D.melanogaster) yellow locus inserted the transposon gypsy y, will cause some tissue y gene inactivation, but some organizations y gene was still active, the reason is that one end of the transposon gypsy There is a insulator sequence. When the gypsy inserted at different positions "/ locus on to the active genes have different effects. This is because the active y gene enhancer controlled by four, when the insulator is inserted just upstream of the promoter, on the shoulder wings (wing blade) and somatic epithelial activation (body cuticle) tissue blocking the gene (from the upstream The enhancer), but does not block the setae (bristles) and tarsal foot (farsal claws) tissues y gene expression (enhancer from downstream). Because some enhancer is located upstream of the promoter, some located downstream, so the effect is not dependent on insulator insulator relative position of the child with the start. Thus, the reason for directional insulator effect has not really understood. Currently there are two loci have been found to affect trans-activation mode insulator function. Gene S2J (Hw) encoding nucleoprotein identification insulator, insulator with its binding only after the insulation. When this gene mutation, although y locus inserted insulator, but losing the insulating effect, y are expressed in all tissues. Another locus is mod (mdg 4), after the gene mutation, its effect coincides with Su (Hw) On the contrary, that these mutants have enhanced insulating effect of the insulating effect of the insulator no directionality be extended , which is blocking the enhancer upstream and downstream sides of the effect. One explanation is that after the first Su (Hw) insulator with DNA combine to make the insulator with an insulating effect. mod (mdg4) with Su (Hw) combine to make insulators lose insulation effect; mutation mod (mdg4) can not be combined with Su (Hw), then insulator but also enhance the insulation. Company Website: www.hjxinrui.com