Untitled - D Ank Unlimited

diversity 232 DNA laddering
Formation of disulfide bond
Cys – SH + HS – Cys
diversity
The presence of numerous lymphocytes with different
antigenic specificities to create a lymphocyte repertoire that
is large and varied. Diversity, which is critical to adaptive
immune responsiveness, is a consequence of structural variability
in antigen-binding sites of lymphocyte receptors for
antigen (antibodies and TCRs).
diversity (D) gene segments
Abbreviated coding sequences between the V and constant
gene segments in the immunoglobulin heavy chain and
T cell receptor β and δ loci together with J segments are
recombined somatically with V segments during lymphocyte
development. The recombined VDJ DNA encodes
the carboxyl terminal ends of the antigen receptor V
regions, including the third hypervariable (CDR) regions.
D segments used randomly contribute to antigen receptor
repertoire diversity.
Dixon, Frank James (1920–2008)
American physician noted for his fundamental contributions
to immunopathology, particularly the role of immune
complexes in the production of disease. He is also known
for his work on antibody formation. Dixon was the founding
director of the Research Institute of Scripps Clinic.
DN thymocytes
Double negative thymocytes that fail to express either CD4
or CD8 molecules. Thus, they have a CD4- CD8- Formation of disulfide bonds from the oxidation of two sulfhydryl groups
and the breaking of disulfide bonds through reduction, leading to sulfhydryl
formation.
surface
phenotype. The four DN thymocyte subpopulations are
designated DN1 through DN4.
DNA binding motif
A nuclear transcription factor binding site variably present
in genomic DNA, such as KB that binds NF-KB and
ISRE (interferon-stimulated response element) that binds
IRFs.
DRI
Oxidation
Cys – S – S – Cys
Breakage of disulfide bond
Cys – S – S – Cys
Cys – SH HS – Cys
Cys – S CH2COO Cys – S
–
CH2COO –
DNA Sequence
Reduction
2(ICH 2 COOH)
DNA-dependent RNA polymerase
An enzyme that participates in DNA transcription. With
DNA as a template, it catalyzes RNA synthesis from the
ribonucleoside-5′-triphosphates.
DNA fingerprinting
A method used to demonstrate short, tandem-repeated
highly specific genomic sequences known as mini satellites.
The probability that two persons would have the
identical DNA fingerprint is only 1 in 30 billion. DNA
fingerprinting has greater specificity than restriction fragment
length polymorphism (RFLP) analysis. Each individual
has a different number of repeats. The insert-free,
wild-type M13 bacteriophage identifies the hypervariable
mini satellites. The sequence of DNA that identifies the
differences is confined to two clusters of 15 base-pair
repeats in the protein III gene of the bacteriophage. The
specificity of this probe, known as the Jeffries probe,
renders it applicable to parentage testing, human genome
mapping, and forensic science. RNA may also be split into
fragments by an enzymatic digestion followed by electrophoresis.
A characteristic pattern for that molecule is
produced and aids in identifying it.
DNA laddering
Endonucleases are activated during apoptosis. Activated
endonucleases nick genomic DNA at internucleosomal
sites to produce DNA fragments. Not all cell types
Protein Sequence
CAG CTT AAG TTT GAA TGT CATTTC TTC AAT Glu Leu Lys Phe Glu Cys His Phe Phe Asn
1001
DR2(15 and 16) c AGG G Pro Trp Val
1002
DNA fingerprinting.
Frank James Dixon.