{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Transcription-07 - Chapter 8 Transcription and...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 8  Transcription and processing  (DRAFT) Expression  of genetic material By  expression  we mean the production of RNAs and proteins. Gene expression is accomplished by the processes: Transcription RNA processing translation The  central dogma  of molecular biology was enunciated by Francis Crick in 1958. The  central dogma The flow of information from loci to proteins The flow is unidirectional Information here means the precise determination of sequence. Transcription Transcription  is the production of an RNA molecule using a DNA molecule as a template. Define  transcript :  The RNA product of transcription. Note the linguistic analogy.  When we transcribe our notes we rewrite them in the same  language.  The information in the nucleotide DNA is copied into a nucleotide chain of RNA.   So the information flows from nucleotide polymer to nucleotide polymer. RNA is produced from the 5’ to 3’ because the 3’OH is necessary for extension. Types of RNA : tRNA  :  transports amino acids to the translation complex and aligns them at the correct location  along the mRNA. rRNA :  Combine with proteins to make ribosomes.  rRna’s do most of the catalytic functions of  the ribosomes.  Recall the definition of  ribozymes . snRNA’s :  small nuclear RNA’s.  combine with specific proteins to form ribonucleoprotein  particles (snRNP’s).  These particles compose the spliceosome that removes introns and splices  exons together. scRNA  small cytoplasmic RNA.  Direct protein traffic within the eukaryotic cell.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Properties of RNA . Usually  single stranded  at production that can then assume  many complex shapes  for many  functions.  More complex shapes than double stranded DNA. It is this ability to assume complex shape that gives RNA its catalytic ability allowing some RNAs  to be  ribozymes .   (Note:  This catalytic ability of RNA is congruent with hypothesis that RNA may have preceded  DNA as the genetic material.) RNA is produced from only one strand of the DNA molecule called the  template strand .   The other strand is called the non template strand. RNA polymerase  is the enzyme that makes the bonds between the RNA monomers. It does not need a primer. The RNA product does not remain base-paired to the Template DNA, the enzyme displaces the  growing chain only a few nucleotides behind where each nucleotide is added. Note rna  polymerase has a helicase property for a dna rna duplex f This allows multiple RNA pols to transcribe the same region at the same time closely behind each  other.
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern