Development of T and B Lymphocytes Flashcards
What is the process by lymphocytes are created called?
Lymphopoiesis
What is a key defining feature of lymphocytes?
Presence of an acceptable antigen receptor
What is the first part of the receptor expressed on a pre-B cell?
Heavy chain
What is the first par of the receptor expressed on a pre-T cell?
Beta-chain
What occurs if an immature B or T cell expresses strong recognition of an antigen?
They are killed
Which region on T and B cells are encoded by a combo of gene segments?
Variable Heavy Light
Variable alpha and beta
How can unlimited variable receptors for T and B cells beta and heavy chains be possible?
V D J gene segments are rearranged in the receptors genome
How are multiple alpha and light chains encoded?
V and J gene segments rearrange and come together
What codes for the C region in both T and B cells?
C region in the genome
What do recombination signal sequences (RSS) do?
They are directly adjacent to the coding sequence of V, D, and J gene segments
What does V(D)J recombinase do?
Recognizes RSS and mediates recombination process
What are RAG-1 and RAG-2?
Recombinase-activating gene
What do RAG-1 and RAG-2 do?
Encode for recombinase activating needed for V(D)J recombinase to work
What is combinatorial diversity?
Movement of the V D J segments adds diversity in receptor chains
What is junctional diversity?
Nucleotides are added or moved at the VD or VDJ segments for added diversity
