antisense (redirected from Antisense elements (genetics))

antisense /an·ti·sense/ (an´te-) (an´ti-sens) referring to the strand of a double-stranded molecule that does not directly encode the product (the sense strand ) but is complementary to it.

Antisense strand of DNA, complementary to the sense (coding) strand and serving as a template for RNA synthesis.

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an·ti·sense (nt-sns, nt-)

adj.

Of or relating to a nucleotide sequence that is complementary to a sequence of messenger RNA. When antisense DNA or RNA is added to a cell, it binds to a specific messenger RNA molecule and inactivates it.

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gene therapy Molecular medicine Treatment of disease by replacing, altering or supplementing the genetic structure of either germline–reproductive or somatic–nonreproductive cells a structure that is absent or abnormal and responsible for disease; any of a group of techniques in molecular biology, in which a gene of interest is manipulated, either by mutational inactivation–eg, the 'knock-out mouse', or by replacement, if it causes a particular disease; GT encompasses any therapy that specifically targets the core defect in inherited diseases, either by affecting somatic cells or germ line cells which are usually inserted into the host's genome; strategies for GT include 1. Introduction of a recombinant retrovirus with the missing gene, the promoter, and the gene regulator sequence in the 'package', and 2. Implantation of the colonies of cells producing the missing factor(s)–eg, α₁-antitrypsin deficiency with the missing enzyme introduced into 'carrier' fibroblasts

Gene therapy strategies

Antibody genes Interfere with cancer-related protein activity in tumor cells

Antisense Block synthesis of proteins encoded by a defective gene in the host

Chemoprotection Add proteins to cells that protect them from the toxic effect of chemotherapy

Immunotherapy Enhance host defense against cancer

Oncogene downregulation Turn off genes involved in uncontrolled growth and metastases of tumor cells

Suicide gene/pro-drug therapy Insert proteins that metabolize normal drugs and ↑ their toxicity to proliferating–ie tumor cells

Tumor suppressor genes Replace defective/deficient cancer-inhibiting genes