R terms

Rapeseed

- a plant widely grown for its industrial oil in the 1940's. In the 1960's breeding efforts led to the removal of two compounds, erucic acid and glucosinolates, changing the plant to an edible oilseed now called canola.

Source: http://pbi-ibp.nrc-cnrc.gc.ca/en/media/glossary.htm

Recombinant DNA

- DNA that is formed through combining DNA from two different sources. Humans direct the formation of recombinant DNA through selective breeding and genetic engineering.

Recombinant DNA (rDNA) technology

- The laboratory manipulation of DNA in which DNA, or fragments of DNA from different sources, are cut and recombined using enzymes. This recombinant DNA is then inserted into a living organism. rDNA technology is usually used synonymously with genetic engineering.

Recombination

- The formation of new combinations of genes. Recombination occurs naturally in plants and animals during the production of sex cells (sperm, eggs, pollen) and their subsequent joining in fertilization. In microbes, genetic material is recombined naturally during conjugation.

Regeneration

- The process of growing an entire plant from a single cell or group of cells.

Regulatory gene

- A gene that codes for a repressor, which in turn regulates the genetic transcription of structural genes in an operon by binding to the operator locus

Repressor

- A protein that binds to the operator locus and thereby inhibits the transcription of adjacent genes by blocking the RNA polymerase from the promoter for those genes

Restriction enzymes

- Bacterial enzymes that cleave DNA at very specific locations.

Restriction map

- A diagram that shows restriction sites (i.e., where a restriction enzyme cleaves DNA) in relation to one another.

Restriction Fragment Lenght Polymorphism (RFLP)

- Term that denotes the differences in molecular weight of homologous fragments of restriction enzyme-digested genomic DNA sometimes observed in two genetically distinct individuals

Ribosomal RNA/rRNA

- The RNA molecule that associates with the ribosomal protein to form the ribosome

Ribosome

- An organelle, consisting of two subunits of RNA and proteins, that synthesizes polypeptide whose amino acid sequences are specified by the nucleotide sequences of the mRNA

Rice

- (genus Oryza) is a plant of the grass family which feeds more than half of the world's human population. Rice cultivation is well suited to countries with low labor costs, but high rainfall as it is very labor-intensive to cultivate and requires plenty of water for irrigation. Rice is the world's third largest crop, behind maize (corn) and wheat.

Source: http://en.wikipedia.org/wiki/Rice

RNA (Ribonucleic acid)

- Like DNA, a type of nucleic acid. There are three major types: messenger RNA, transfer RNA, and ribosomal RNA. All are involved in the synthesis of proteins from the information contained in the DNA molecule.

RNAi (RNA interference)

- A gene silencing phenomenon whereby double-stranded RNAs trigger the specific degradation of a homologous mRNA.

Source: http://www.uark.edu/ua/ricecap/ricecapgloss.htm

RNA polymerase

- The enzyme responsible for the transcription of the information encoded in the DNA into RNA; also called transcriptase

Rubber

- A tree belonging to the family Euphorbiaceae. Of major economical importance due to its sap (or latex) which the primary source of natural rubber.

Source: http://en.wikipedia.org/wiki/Rubber_tree