What is rRNA polymerase?

Are all three types of RNA coded by the same genes?

There are different types of genes for encoding three types of RNA. Protein coding genes are transcribed by RNA polymerase II to yield mRNA. Ribosomal RNA (rRNA) are transcribed by RNA polymerase I. Likewise, transfer RNA (tRNA) are transcribed by polymerase III.

What is RNA produced by?

Ribosomal RNA (rRNA) production represents the most active transcription in the cell. Synthesis of the large rRNA precursors (35-47S) can be achieved by up to 150 RNA polymerase I (Pol I) enzymes simultaneously transcribing each rRNA gene. In this paper, we present recent advances made in understanding the regulatory mechanisms that control elongation. Built-in Pol I elongation factors, such as Rpa34/Rpa49 in budding yeast and PAF53/CAST in humans, are instrumental to the extremely high rate of rRNA production per gene. rRNA elongation mechanisms are intrinsically linked to chromatin structure and to the higher-order organization of the rRNA genes (rDNA). Factors such as Hmo1 in yeast and UBF1 in humans are key players in rDNA chromatin structure in vivo. Finally, elongation factors known to regulate messengers RNA production by RNA polymerase II are also involved in rRNA production and work cooperatively with Rpa49 in vivo.

How much RNA is in bacteria?

There is approximately 100-155 fg/cell of protein and ~20 fg/cell of RNA based on Cox, R.A. (2004) Quantitative relationships for specific growth ratios and macromolecular compositions of Mycobacterium tuberculosis, Streptomyces coelicolor A3(2) and Escherichia coli B/r: an integrative theoretical approach. Microbiology. 150:1413-26. As a side, there is also ~4.2 fg/cell of DNA based on Kubitschek, HE and Friedman, MC (1971) Chromosome replication and the division cycle of Escherichia coli B/r. Journal of Bacteriology. 107:95-99.

What type of RNA is most abudant?

Ribosomal RNA. rRNA.

What is the r role of 23S rRNA of 50S RNA?

the 50S rRNA particle forms the large subunit of E. coli ribosomes while the 23S rRNA is a component of the 50S rRNA.

What is RNA polymerase and what is its job?

The RNA polymerases are huge multi-subunit protein complexes. Three kinds are found in eukaryotes: * RNA polymerase I (Pol I).It transcribes the rRNA genes for the precursor of the 28S, 18S, and 5.8S molecules (and is the busiest of the RNA polymerases). * RNA polymerase II (Pol II; also known as RNAP II).It transcribes protein-encoding genes into mRNA (and also the snRNA genes). * RNA polymerase III (Pol III).It transcribes the 5S rRNA genes and all the tRNAgenes.

RRNA is always attached to the rough ER?

No . cytoplasm also contain rrna .

What is produced in transcription?

Transcription in Prokaryotes requires one enzyme for the 4 stages of: 1) binding of RNA polymerase holoenzyme at promoter sites, 2) initiation of polymerization, 3) chain elongation, and 4) chain termination Transcription in Eukaryotes requires three RNA polymerases I, II, and III transcribe rRNA, mRNA, and tRNA genes respectively.

Differences between DNA polymerase and RNA polymerase?

A polymerase is an enzyme that catalyzes the conversion of free nucleotides into a single strand. DNA polymerase differs from RNA polymerase in two major respects: * Like all enzymes, DNA polymerase is substrate-specific. DNA polymerase cannot extend a single strand of DNA; it needs at least a short segment of double-stranded DNA at the outset. * As its name implies, DNA polymerase incorporates deoxyribonucleotides into the new strand. RNA polymerase incorporates ribonucleotides. These differences mean that DNA polymerase is active when new DNA strands are formed, as in DNA replication, and RNA polymerase is active when new RNA is formed, as in transcription. Before DNA replication can begin, the two strands must uncoil, so that each can form a template for free nucleotides to attach to. But DNA polymerase cannot get started with a single strand! In vivo(in the cell) RNA polymerase, which is active in the presence of single-stranded DNA, catalyzes the incorporation of a handful of nucleotides into a new strand. The short length of double-stranded nucleic acid that is produced enables DNA polymerase to swing into action. This still leaves a potential difficulty: the nucleotides incorporated in the presence of RNA polymerase are the wrong sort (ribonucleotides). They are subsequently replaced by DNA polymerase. In vitro (during PCR, the polymerase chain reaction) a primer, specially synthesized in a laboratory, attaches to a specific segment of single-stranded DNA, and the DNA polymerase takes over from there. The primer consists of a short length of single-stranded DNA that uniquely complements a specific DNA segment that is targeted for amplification, for example for forensic analysis.In practice, there are several different DNA polymerases and RNA polymerases in an organism.

What is rRNA?

Ribosomal ribonucleic (rRNA) is RNA that forms part of ribosomes. rRNA plays a role in translation, in which mRNA's codons and tRNA's anticodons are used to build a protein.

Is the enzyme that allows replication to occur DNA polymerase or RNA polymerase?

DNA polymerase replicated DNA. RNA polymerase creates mRNA to be used in protein synthesis. RNA polymerase does not replicated DNA.

What is the source of the polymerase used in polymerase chain reaction?

Taq polymerase, the enzyme used frequently in Polymerase Chain Reaction, is extracted from Thermophilus aquaticus, a thermophilic bacteria.