Biomaterial Database

Isopentenyladenosine deficient tRNA from an antisuppressor mutant of Saccharomyces cerevisiae. 1978

H Laten, and J Gorman, and R M Bock

We have isolated a mutant of Saccharomyces cerevisiae that contains 1.5% of the normal tRNA complement of isopentenyladenosine (i6A). The mutant was characterized by the reduction in efficiency of a tyrosine inserting UAA nonsense suppressor. The chromatographic profiles of tRNATyr and tRNASer on benzoylated DEAE-cellulose are consistent with the loss of i6A by these species. Transfer RNA from the mutant exhibits 6.5% of the cytokinin biological activity expected for yeast tRNA. Transfer RNAs from the mutant that normally contain i6A accept the same levels of amino acids in vitro as the fully modified species. With the exception of i6A, the level of modified bases in unfractionated tRNA from the mutant appears to be normal. The loss of i6A apparently affects tRNA's role in protein synthesis at a step subsequent to aminoacylation.

UI	MeSH Term	Description	Entries
D007541	Isopentenyladenosine	N(6)-[delta(3)-isopentenyl]adenosine. Isopentenyl derivative of adenosine which is a member of the cytokinin family of plant growth regulators.	N(6)-(delta(2)-Isopentenyl)Adenosine
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D011687	Purines	A series of heterocyclic compounds that are variously substituted in nature and are known also as purine bases. They include ADENINE and GUANINE, constituents of nucleic acids, as well as many alkaloids such as CAFFEINE and THEOPHYLLINE. Uric acid is the metabolic end product of purine metabolism.
D011743	Pyrimidines	A family of 6-membered heterocyclic compounds occurring in nature in a wide variety of forms. They include several nucleic acid constituents (CYTOSINE; THYMINE; and URACIL) and form the basic structure of the barbiturates.
D000241	Adenosine	A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.	Adenocard,Adenoscan
D012343	RNA, Transfer	The small RNA molecules, 73-80 nucleotides long, that function during translation (TRANSLATION, GENETIC) to align AMINO ACIDS at the RIBOSOMES in a sequence determined by the mRNA (RNA, MESSENGER). There are about 30 different transfer RNAs. Each recognizes a specific CODON set on the mRNA through its own ANTICODON and as aminoacyl tRNAs (RNA, TRANSFER, AMINO ACYL), each carries a specific amino acid to the ribosome to add to the elongating peptide chains.	Suppressor Transfer RNA,Transfer RNA,tRNA,RNA, Transfer, Suppressor,Transfer RNA, Suppressor,RNA, Suppressor Transfer
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D013489	Suppression, Genetic	Mutation process that restores the wild-type PHENOTYPE in an organism possessing a mutationally altered GENOTYPE. The second "suppressor" mutation may be on a different gene, on the same gene but located at a distance from the site of the primary mutation, or in extrachromosomal genes (EXTRACHROMOSOMAL INHERITANCE).	Suppressor Mutation,Genetic Suppression,Genetic Suppressions,Mutation, Suppressor,Mutations, Suppressor,Suppressions, Genetic,Suppressor Mutations