Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
a thread or fiber or a structure resembling one.
antisense strand the strand of a double-stranded nucleic acid that is complementary to the sense strand; in DNA it is the template strand on which the mRNA is synthesized.
sense strand the strand of a double-stranded nucleic acid that encodes the product; in DNA it is the strand that encodes the RNA, having thus the same base sequence except changing T for U in the RNA. See also antisense strand.
the strand of DNA complementary to the one bearing the genetic message and from which it may be reconstructed; a DNA sequence complementary to a portion of mRNA; used as potential therapeutic agent to stop transcription or translation of pathogens or inappropriately expressed host gene.
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.
gene therapyMolecular 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
Pertaining to the strand of a double-stranded DNA or RNA molecule that is complementary to the sense strand.