Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/15

Click to flip

15 Cards in this Set

  • Front
  • Back
Germ-line theories
theories that explain antibody diversity by postulating that all antibodies are encoded in the host chromosomes
Somatic-variation theories
theories maintaining that the genome contains a small number of immunoglobulin genes from which a large number of antibody specificities are generated in somatic cells by mutation or recombination
J (joining)gene segment
the part of a rearranged immunoglobulin or T-cell receptor gene that joins the variable region to the constant region and encodes part of the hypervariable region. There are multiple J gene segments in germ-line DNA, but rearrangement leaves only one in each functional rearranged gene
Signal peptide (leader peptide)
a small sequence of amino acids, also called the leader sequence, that guides the heavy or light chain through the endoplasmic reticulum and is cleaved from the nascent chains before assembly of the finished immunoglobulin molecule
V (variable) gene segment
the 5; coding portion of rearranged immunoglobulin and T-cell receptor genes. There are multiple V gene segments in germ-line DNA, but gene rearrangement leaves only one segment in each functional gene
D (diversity) gene segment
that portion of a rearranged immunoglobulin heavy-chain gene or T-cell receptor gene that is situated between the V and J gene segments and encodes part of the hypervariable region. There are multiple D gene segments in germ-line DNA, but gene rearrangement leaves only one in each functional rearranged gene
Pseudogene
nucleotide sequence that is a stable component of the genome but is incapable of being expressed. They are thought to have been derived by mutation of ancestoral active genes
Recombination signal sequences (RSSs)
highly conserved heptamer and nonamer nucleotide sequences that serve as signals for the gene rearrangement process and flank each germline V, D, and J segments
One-turn recombination signal sequences
immunoglobulin gene-recombination signal sequences separated by an intervening sequence of 12 base pairs
Two-turn recombination signal sequences
immunoglobulin gene recombination signal sequences separated by an interveneing sequence of 23 base pairs
V(D)J recombinase
the set of enzymatic activities that collectively bring about the joining of gene segments into a rearranged V(D)J unit
Recombination-activating genes (RAG-1 and RAG-2)
two closely linked genes, RAG-1 and RAG-2, that encode proteins essential for the rearrangement of immunoglobulin gene segments in the assembly of a functional immunoglobulin gene
Terminal deoxynucleotidyl transferase (TdT)
an enzyme that adds deoxynucleotide triphophates to the 3' ends of DNA
P region nucleotides
P-addition is the addition of nucleotides from cleaved hairpin loops formed by the junction of V-D or D-J gene segments during Ig or TCR gene rearrangements
N region nucleotides
N-addition is the adition of nucleotides by terminal deoxyribonucleotidyl transferase during the process of D-J joining or V-to-DJ joining