Search Results

Search Results

Showing 1-11 of 11 Resources
  • Regulation of Eukaryotic DNA Transcription

    Regulation of Eukaryotic DNA Transcription

    Animations

    (2 min 5 sec) General transcription factors, activators, and repressors interact to regulate the transcription of eukaryotic DNA into RNA.

  • Dengue Virus Life Cycle

    Dengue Virus Life Cycle

    Animations

    (4 min 12 sec) Dengue virus has sophisticated mechanisms for entering a cell, for replicating its RNA genome, and for translating proteins.

  • HIV life cycle

    HIV life cycle

    Animations

    (4 min 52 sec) How HIV infects a cell and replicates itself using reverse transcriptase and the host's cellular machinery.

  • AZT blocks reverse transcriptase

    AZT blocks reverse transcriptase

    Animations

    (1 min 46 sec) HIV's reverse transcriptase mistakes AZT for thymidine. Once incorporated, AZT stops reverse transcription.

  • Translation (advanced detail)

    Translation (advanced detail)

    Animations

    (3 min 4 sec) Messenger RNA (mRNA) carries DNA's genetic information to the ribosome, where it is translated into a sequence of amino acids. mRNA is fed into the ribosome, and it is positioned so that it can be read in groups of three letters, known as codons. Each mRNA codon is matched against the transfer RNA molecule's anti-codon. If there is a match, the amino acid carried by the transfer RNA is added to the growing protein chain. Also available in Spanish.

  • Translation (basic detail)

    Translation (basic detail)

    Animations

    (2 min 6 sec) The ribosome is a molecular factory that translates the genetic information in RNA into a string of amino acids that becomes a protein. Inside the ribosome, the genetic code of the RNA is read three letters at a time and compared with the corresponding code on a transfer molecule. When a match occurs between the codes, the amino acid carried by the transfer molecule is added to the growing protein chain. Also available in Spanish.

  • DNA transcription (advanced detail)

    DNA transcription (advanced detail)

    Animations

    (1 min 55 sec) The process of copying DNA into messenger RNA (mRNA) is called transcription. Transcription factors assemble at the promoter region of a gene, bringing an RNA polymerase enzyme to form the transcription initiation complex. Activator proteins at the enhancer region of DNA then activate the transcription initiation complex. RNA polymerase unzips a small portion of the DNA and copies one strand into an mRNA molecule. Also available in Spanish.

  • DNA transcription (basic detail)

    DNA transcription (basic detail)

    Animations

    (1 min 55 sec) The first phase of the process of reading DNA information to make proteins starts with a molecule unzipping the DNA. The molecule then copies one of the strands of DNA into a strand of RNA, a close cousin of DNA. This process is called transcription. Also available in Spanish.

  • mRNA splicing

    mRNA splicing

    Animations

    (39 sec) Once a gene has been transcribed into messenger RNA (mRNA), it is edited in a process called splicing. Noncoding regions called introns are removed, leaving protein-coding regions called exons.

  • Recombination of Viral Genome

    Recombination of Viral Genome

    Animations

    (3 min 5 sec) When two different strains of influenza infect a single cell, their genetic material can mix freely, resulting in a new third strain of influenza.

  • RNA Folding

    RNA Folding

    Animations

    (33 sec) Since RNA is single-stranded, it can fold upon itself and form structures that are protein-like in both appearance and functionality.