Human Genetics Unit 3

antiparallelism

the head to toe orientation of two nucleotide chains of the dna strands of double helix

chromatin

dna and its complementary protein

complementary base pairs

pairs of dna bases that form hydrogen bonds

deoxyribose

5 carbon sugar that is part of dna nucleotide

dna polymerase

enzyme which adds new base pairs onto replicated dna, correcting mismatched pairs

histone

protein which dna coils around in regular pattern

ligase

enzyme that catalyzes the formation of covalent bonds between phosphate backbone and nucleic acid

next generation sequencing

sequencing millions of small pieces of DNA simultaneously in order to reconstruct a genome sequence

nucleosome

unit of chromatin structure consisting of DNA coiled around a octect of histone proteins

nucleotide

the building blocks of a nucleic acid, consisting of a phosphate group, nitrogenous base, and a 5 carbon sugar

polymerase chain reaction (pcr)

a nucleic acid amplification technique in which a dna sequence is replicated in a test tube. it is used to rapidly produce many copies of a specific dna sequence

purine

a nuclei acid base with a double ring structure (adenine and guanine)

pyrimidine

nucleic acid with a single ring structure (cytosine, thymine, and uracil)

replication fork

locally opened portion of a replicating dna double helix

ribose

5 carbon sugar in rna

semiconservative replication

dna synthesis along each separate strand of the double helix

sugar phosphate backbone

the rails of a dna double helix, consisting of alternating deoxyribose and phosphate groups, oriented opposite of each other

alternative splicing

assembling subsets of the exons of a gene which increases the # and diversity of proteins it encodes

amino acids

small organic molecule that is a protein building block, consisting of amino acid group, a hydrogen, and variable r group

anticodons

a three base sequence on one loop of a trna that is complementary to an mrna codon and connects the appropriate amino acids to its mrna

chaperone protein

protein that binds a polypeptide and guides folding

coding strand

strand of dna double helix for a gene from which rna is not transcribed

codon

continous triplet of mrna that specifies a particular amino acid

conformation

the three dimensional shape of a protein molecule

exon

part of a gene and its corresponding mrna that encodes amino acids

frameshift mutation

a mutation that alters a gene’s reading frame

genetic code

correspondence between specific mrna triplets and amino acids

intron

part of a gene that is transcribed but is excised from the mrna before translation into protein

isoform

an alternate version of a protein that arises from a certain combination of translated exons

nonsynonymous codons

dna triplets that specify different amino acids

open reading frame

dna sequence that does not have a stop codon

polypeptide

long chain of amino acids. a protein consists of one or more polypeptides

primary structure

amino acid sequence of a protein

prion

infectious protein

promoter

control dna sequence that signals the start of a gene

proteasome

a multiprotein cellular structure with a tunnel like shape through which misfolded or excess proteins pass and are dismantled

quaternary structure

protein that has more than one polypeptide chain or subunit

reading frame

point in the dna sequence from which continuous triplets encode amino acids of a protein. a dna sequence has three reading frames

ribosomal rna

rna that comprises ribosomes

rna polymerase

enzyme that adds nucleotides to a growing rna chain

secondary structure

folds in a polypeptide caused by attractions between amino acids close together in the primary structure

synonymous codons

dna triplets that specify the same amino acid

template strand

dna strand carrying information to be transcribed

tertiary structure

folds in polypeptide caused by interactions between amino acids and water, drawing together amino acids that are far apart in the primary structure

transcription factors

proteins that form a structure that binds dna a certain sequences, initiating transcription at specific sites on chromosome

chromatin remodeling

adding or removing chemical groups to or from histones, which can alter gene expression

microRNA

a 21- or 22- base long RNA that binds to certain mRNAs, blocking their translation into protein

proteomics

cataloging all of the proteins a specific organelle or cell type makes under specific conditions

single cell transcriptomics

identifying all of the mRNA molecules that an individual cell produces at a given time and circumstance

transcriptome

the collection of mRNA molecules in a cell

Friedrich Miescher

1871 Swiss Physician who isolated nuclei from blood cells (nuclein or later knowns as nucleic acid)

Archibald Garrod

1902 english physician who linked inheritance of inborn errors of metabolism with the lack of particular enzymes

Frederick Griffith

1928 english microbiologist who discovered the phenamena of transformation (bacteria sharing their dna)

Avery, MacLeod, and McCarty

1944 american physicians who identified dna is a transforming principle

Alfred Hershey and Martha Chase

1953 american microbiologists who confirmed that DNA is the genetic material through their blender experiments

Phoebus Levene

russia-american biochemist who identified the parts of a nucleotide

Erwin Chargaff

1951 complemetary base pairing (chargaffs rule)

Rosalind Franklin, Raymond Gosling and Maurice Wilkins

xray diffraction to distinguish the structure of DNA, revealing its double helix shape. (a form and b form)

James Watson and Francis Crick

Developed the double helix model of DNA structure, using data from Franklin and Chargaff.