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The term "central dogma" of molecular biology is often taken to mean the flow of information from the DNA in the nucleus of the cell, into messenger RNA via transcription, and thence into proteins (more correctly, polypeptide chains) via translation at ribosomes in the cytoplasm.

1. The DNA replicates its information in a process that involves many enzymes: replication.

2. The DNA codes for the production of messenger RNA (mRNA) during transcription.

3. In eukaryotic cells, the mRNA is processed(essentially by splicing) and migrates from the nucleus to the cytoplasm.

4. Messenger RNA carries coded information to ribosomes. The ribosomes "read" this information and use it for protein synthesis. This process is called translation.

* * *

If this question is taken to refer to the above sense of "central dogma", and the "challenge" therefore to the "reverse" flow of information: from RNA to DNA, that was found to be routine in retroviruses (such as HIV, which causes AIDS), using the enzyme reverse transcriptase. The names of David Baltimoreand Howard Temin are particularly associated with the discovery of this enzyme.

In fact, this question opens a can of worms! It's all to do with what people take the term "central dogma" to mean.

In 1958 Francis Crick coined two terms for two ideas that were then considered fruitful in guiding future research. This was five years after the publication of Watson and Crick's double-helix model for DNA, and three years before the genetic code began to reveal itself through experiments by Nirenberg and Matthaei ("polyU" coding for phenylalanine, etc.) and by Crick and Brenner (the code consisting of three nucleotides).

The two ideas were:

1

The sequence of residues in DNA informs the biosynthesis of proteins (we would now say polypeptides), specifically the sequence of residues (amino acids). Logically enough, Crick called this idea the sequence hypothesis.

2

Once information (about the sequence of residues) has passed into a protein, it does not come out; in other words, the amino acid sequence of a polypeptide chain does not influence the synthesis of DNA, RNA, or other polypeptide chains. Crick called this the central dogma.

In later years, among other things:

Watson published a book, Molecular biology of the gene, in which he confused Crick's two points, using the term "central dogma" in a way that relates it to the sequence hypothesis. Watson did not use the term "sequence hypothesis". There has now developed a widespread myth, especially associated with the United States, that the idea of the sequence hypothesis was calledby Crick the "central dogma".

Some people who had not read Crick's paper, and knew little of his mind and modus operandi as a scientist, accused him of trying to stifle research, by being "dogmatic" that information could flow only from DNA to RNA to protein, and never in the reverse direction. Crick never said that, as a read of his 1958 paper confirms.

Crick wrote a note, published in Nature in 1970, trying to put the record straight. He particularly mentioned by name Barry Commoner as someone who had misquoted him (and, implicitly, someone who had used the misquotation to draw false conclusions about Crick's reasoning and motives).

Crick much later admitted that when he chose the word "dogma" he thought it was more or less close in meaning to "hypothesis".

Does Crick's central dogma hold true? NO. 1.) A viruses genome consists of RNA. 2.) The process of DNA to RNA to protein can actually be reversed (aka complementary DNA).

Prions do not challenge Crick's dogma. The modifications to proteins that prions effect are to secondary structure (coiling and so on), not to the primary structure (the amino acid sequence).

***

Crick's "Central Dogma" has been contradicted by countless experimental facts. However, "facts don't kill theories - only more advanced theories kill obsolete theories". "The Principle of Recursive Genome Function" (Pellionisz, 2008) showed that by retiring the old mistaken axioms of BOTH JunkDNA and Central Dogma we accomplish the theoretical breakthrough towards "Recursive Genome Function".

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Q: What is the central dogma and who challenged it?
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Related questions

Is there any online quiz for central dogma of molecular biology?

Yes, there are a few quizzes for central dogma under the related links.


What is central Dogma transcription and translation?

The central dogma states. DNA -> RNA -> proteins


How is retrovirus reproduction is an exception to central dogma?

The "central dogma" states information goes from DNA to RNA to Protein in a retrovirus it goes from RNA to DNA back to RNA to Protein. The central dogma as it is called has so many exceptions now that it is no longer considered central.


What is the central dogma of DNA and why is it important?

The central dogma of DNA, also known as the central dogma of molecular biology describes the sequence DNA -> RNA -> Protein. This is important because it shows the process of creating proteins from DNA and is the process by which cells regulate their functions.


What describes the flow of genetic information?

Central Dogma.


What is central dogma in a short brief simply?

Flow of information for the synthesis of protein through a series of processes like transcription and translation is called central dogma.


Is both DNA and RNA involved in the central dogma of biology?

Yes. The central dogma of biology postulates: DNA < > RNA > Proteins


Who coined central dogma?

Francis Crick.


What is central dogma?

The central dogma of molecular cell biology which explains the one way flow of information in a cell. DNA --> RNA --> Protein


Why central dogma called central dogma?

That was a somewhat satirical name Francis Crick gave to the process that he helped develop an elucidation of. There are no true dogmas in biology, though RNA -> DNA -> protein is very much the general process, reverse transcription rather " destroys " the central dogma.


What is a sentence using the word dogma?

Central dogma of biology is life. This is one of many examples for sentence use.


What is protein synthesis also known as?

central dogma


What describes the flow genetic information?

Central Dogma.


What are 3 process involved in the central dogma?

replication, transcription and translation.


What is the central dogma of biochemistry?

The "central dogma" was that the flow of information always went from DNA to RNA to protein. This assumption was discarded with the discovery of reverse transcriptase, which allowed information to move from RNA to DNA.


What is the central dogma of gene expression?

Transcription is the first part of the central dogma of molecular biology: DNA โ†’ RNA


What is an exception to the central dogma?

A brief on the central dogma first:double stranded DNA >> single stranded RNA >> proteinsSome exceptions (or violations) to the central dogma of molecular biology are:Some microorganisms only contain RNA (and have no DNA)Some have RNA that is reverse transcripted into DNA and then back into RNASome viruses have single stranded DNASome viruses have double stranded RNA


Central dogma stages?

The Central Dogma explains why DNA is important. DNA is transcribed into MRNA (messenger RNA) = Proteins. Proteins tell all biological systems how to function, which also express traits.


Is central dogma of molecular biology can be reversed or not?

it should be reversed


What is the the theory that describes protein building in this order?

Central Dogma


Why is the Central dogma of molecular biology in human development?

Central dogma dictates DNA-->mRNA-->proteins.This explain that a gene or DNA make mRNA first. the mRNA transported to cytoplasm for protein synthesis.


How does information flow according to the central dogma?

DNA to RNA to Protein


What part of the central dogma that occurs in the cytoplasm of eukaryotic cells?

translation


Are both DNA and rna are involved in the central dogma of biology?

Yes


What are involved in the updated central dogma?

The central dogma of molecular biology was first proposed by Francis Crick in 1956. The updated view involves the new types of functional RNAs that DNA has been able to encode, due to the results in recent genomic studies.