self-replicating

(adjective)

able to generate a copy of itself

Related Terms

Examples of self-replicating in the following topics:

  • Elements of Life

    • A fundamental question is about the nature of the first self-replicating molecule.
    • Since replication is accomplished in modern cells through the cooperative action of proteins and nucleic acids, the major schools of thought about how the process originated can be broadly classified as "proteins first" and "nucleic acids first. " The principal thrust of the "nucleic acids first" argument is as follows:
    • The polymerization of nucleotides into random RNA molecules might have resulted in self-replicating ribozymes (RNA world hypothesis).

  • Evolution of Viruses

    • A third hypothesis posits a system of self-replication similar to that of other self-replicating molecules, probably evolving alongside the cells they rely on as hosts; studies of some plant pathogens support this hypothesis.

  • Viroids

    • Some viroids are ribozymes, having catalytic properties which allow self-cleavage and ligation of unit-size genomes from larger replication intermediates.
    • Virusoids are similar to viroids in size, structure, and means of replication.
    • Replication occurs in the chloroplasts of plant cells.
    • Key features of replication include no helper virus required and no proteins are encoded for.
    • Relate the structure and replication of a viroid to its ability to cause diseases in plants

  • General Features of Virus Replication

    • Viruses must first penetrate and enter the cell before viral replication can occur.
    • Replication between viruses is varied and depends on the type of genes involved.
    • Replication of viruses depends on the multiplication of the genome.
    • Following the structure-mediated self-assembly of the virus particles, some modification of the proteins often occurs.
    • Whenever the host divides, the viral genome is also replicated.

  • Mu: A Double-Stranded Transposable DNA Bacteriophage

    • It can then use transposition to initiate its viral DNA replication.
    • A transposable element (TE) is a DNA sequence that can change its relative position (self-transpose) within the genome of a single cell.
    • Mu phage transposition is the best known example of replicative transposition.
    • Replicative transposition is a mechanism of transposition in molecular biology, proposed by James A.
    • In this mechanism, the donor and receptor DNA sequences form a characteristic intermediate "theta" configuration, sometimes called a "Shapiro intermediate. " Replicative transposition is characteristic to retrotransposons and occurs from time to time in class II transposons.

  • DNA Replication in Eukaryotes

    • There are specific chromosomal locations called origins of replication where replication begins.
    • Because two helicases bind, two replication forks are formed at the origin of replication; these are extended in both directions as replication proceeds creating a replication bubble.
    • Eukaryotic chromosomes have multiple origins of replication, which initiate replication almost simultaneously.
    • Each origin of replication forms a bubble of duplicated DNA on either side of the origin of replication.
    • Once all the template nucleotides have been replicated, the replication process is not yet over.

  • DNA Replication in Prokaryotes

    • There are specific nucleotide sequences called origins of replication where replication begins.
    • Two replication forks at the origin of replication are extended bi-directionally as replication proceeds.
    • A primer provides the free 3'-OH end to start replication.
    • The replication fork moves at the rate of 1000 nucleotides per second.
    • A replication fork is formed when helicase separates the DNA strands at the origin of replication.

  • Viral Replication and Gene Expression

    • RNA viruses are classified into distinct groups depending on their genome and mode of replication.
    • Replication of viruses primarily involves the multiplication of the viral genome.
    • Replication also involves synthesis of viral messenger RNA (mRNA) from "early" genes (with exceptions for positive sense RNA viruses), viral protein synthesis, possible assembly of viral proteins, then viral genome replication mediated by early or regulatory protein expression.
    • Viral replication usually takes place in the cytoplasm .
    • Viruses that replicate via RNA intermediates need an RNA-dependent RNA-polymerase to replicate their RNA, but animal cells do not seem to possess a suitable enzyme.

  • Chromosomes and DNA Replication in the Archaea

    • The cell division process is controlled by the cell cycle; the chromosomes within the Archaea are replicated to produce two daughter chromosomes.
    • The circular chromosomes contain multiple origins of replication, using DNA polymerases that resemble eukaryotic enzymes.
    • DNA replication, similar in all systems, involves initiation, elongation, and termination.
    • The replication of DNA, beginning at the origins of replication present on the circular chromosomes, requires initiator proteins.
    • The DNA replication system in Archaea, similar to all systems, requires a free 3'OH group before synthesis is initiated.

  • Microbial Evasion of Phagocytosis

    • Pathogenic bacteria and protozoa have developed a variety of methods to resist attacks by phagocytes (phagocytosis), and many actually survive and replicate within phagocytic cells.
    • Fourth, some bacteria can avoid contact with phagocytes by tricking the immune system into "thinking" that the bacteria are "self" cells.
    • Other pathogens, such as Leishmania, create a highly-modified vacuole inside the phagocyte, which helps them persist and replicate.