Electric porcelain insulators refer to porcelain based electrical insulation materials.



【 Classified by voltage level 】: High voltage, low voltage



Production capacity

The function of insulators is directional, which was discovered in fruit fly experiments. The insertion of transposon gypsy into the yellow locus y of fruit fly (D. melanogaster) results in the inactivation of the y gene in some tissues, but the y gene remains active in some tissues due to the presence of an insulator sequence at one end of the transposon gypsy. When gypsy is inserted at different positions in the "/" locus, it has different effects on gene activity. This is because the activity of y gene is regulated by four enhancer. When the insulator is inserted just upstream of the promoter, it blocks the activation of the gene (from the upstream enhancer) in the wing blade and body cuticle tissues, but does not block the expression of y gene (from the downstream enhancer) in the tissues of the bristles and the tarsal claws.

Since some enhancer are located upstream of the starter and some are located downstream, the effect of the insulator does not depend on the relative position of the insulator and the starter. Therefore, the reason for the directionality of the insulator effect has not been truly understood. It has been found that two loci affect the function of insulators through trans activation. The nuclear protein recognition insulator encoded by the S2J (Hw) gene of the suspension type high-voltage glass toughened insulator has insulation effect only after the insulator is combined with it. When the gene mutates, although an insulator is inserted into the y locus, it loses its insulation effect and y is expressed in all tissues. The other locus is mod (mdg4). After the mutation of this gene, its effect is just opposite to Su (Hw), that is, these mutants enhance the insulation effect, making the insulation effect of insulators no longer directional and expanding, that is, blocking the effect of enhancer on both upstream and downstream sides. One explanation is that Su (Hw) first binds to the insulator DNA, resulting in an insulation effect on the insulator. The combination of mod (mdg4) and Su (Hw) causes the insulator to lose its insulation effect; The mutated mod (mdg4) cannot bind to Su (Hw), thus enhancing the insulation effect of the insulator.