RNA and Protein Synthesis RNA Compare RNA to

RNA and Protein Synthesis

RNA • • Compare RNA to DNA Different sugar (ribose) Single strand instead of double 1 different nitrogen base – Uracil is in RNA, Thymine is not

DNA IS…. . • Nucleic acid (What are other classes of chemical compounds of life? ) • Stores/transmits genetic information from 1 generation to next • Controls all daily operations/functions of the cell • Base Pairing Rule is…. .

Why RNA? • Book – RNA is a “disposable” copy of DNA • RNA is a “working copy” • DNA is the master set of plans to operate the cell, organism, RNA is a subset, part of the plan to perform a specific function. • DNA is kept safe in the vault, RNA can move out of the safe area and be used at different locations.

TYPES of RNA • Messenger RNA (m. RNA) – Copy of code from DNA to work site • Ribosomal RNA (r. RNA) – RNA that is part of the composition of ribosomes • Transfer RNA (t. RNA) – RNA that transfers/brings correct amino acid to a ribosome during protein building (synthesis)

Transcription • Process where a segment of DNA is copied to make an RNA segment – RNA polymerase separates the DNA strands – Then uses one of the DNA strands as a template to make a complementary copy of RNA – DNA zips back together

Transcription • If the DNA sequence is GTACATTAG, what is the RNA sequence? • CAUGUAAUC

Transcription Animation! • http: //www. stolaf. edu/people/giannini/flash animat/molgenetics/transcription. swf

The Genetic Code • A protein is made up of many amino acids • There are 20 different amino acids • Different amounts and different sequences of amino acids mean many different protein possibilities • The sequence of nitrogen bases in m. RNA is the code for creating various proteins • Language of m. RNA (base sequences) is the genetic code

CODON • A “word” of 3 nitrogen bases is a code to make an amino acid. • This 3 letter code is called a codon • AUCCAGGAU is a possible sequence. • How many codons in above sequence? • 4 nitrogen bases, three positions, 4 x 4 = 64 different “words” in the code. • 20 amino acids, start, stop

Another Transcription Animation!! • http: //www. concord. org/~btinker/workbenc h_web/models/euk. Transcription. swf

Review • • • Codons are the m. RNA “words” to make… Amino acids are used to make… Proteins If there is only 1 way to make tryptophan, and 4 ways to make alanine, what can you infer?

Review • If alanine is used in more proteins than tryptophan, how is it good that there are more ways to make alanine? • How many proteins are being made at any one time in any or your cells?

Translation • Decoding of the m. RNA message in the creation of a protein (polypeptide) chain • m. RNA attaches to a ribosome. • Codon moves through ribosome, is read. • t. RNA brings proper amino acid to the ribosome • Process repeats until protein is finished

Anticodon • 3 nitrogen bases on the t. RNA that is the opposite of a specific codon (for a particular amino acid) • If the m. RNA codon is AGC, the t. RNA anticodon is • UCG

Transcription vs. Translation • Copy the last section, Genes and Proteins, of section 12 -3, page 306 in your notes. • This is transcription – you are copying in your own writing (DNA is the book font, your copy is printing – similar to differences from T to U. • Copy Genes and Proteins, of section 12 -3, page 306 in your notes, in Spanish, French, German • This is translation, from one language to another. • The language of nitrogen bases translated to the language of amino acids.

Animation • http: //vcell. ndsu. edu/animations/translation /movie-flash. htm

Mutations • A change in genetic material • Mistake in copying DNA • Mistake in copying RNA

Gene Mutations • Single amino acid mutation, single nucleotide or small number of nucleotides • Substitution – probably not a huge problem • Deletion • Insertion – both can be a bigger problem, might ruin the entire message

Mutation Types • • • Substitution – Original – ATCGCC Mutated – ACCGCC Deletion – Original – ATCGCC Mutated – ACGCC Insertion – Original – ATCGCC Mutated - AATCGCC

What does a subsititution do? • Should be ATACAGCATGAG • Is GTACAGCATGAG • ATG ---UAC GTA---CAU • UAC = Tyrosine CAU = Histidene

Chromosomal Mutations • Change or shift in entire chromosome • Could be deletions duplications switching of order • Autosomal – mutation in one of the nonsex chromosomes (X or Y)

Sex Linked Genes • Alleles on the X or Y chromosome • Humans have many more genes on the X than the Y, so there are many more Xlinked traits than Y-linked traits. • Males are more likely to have recessive traits that are linked to the X chromosome.

Mutation Significance • Many are neutral • Some can be harmful to a cell, or the entire organism – cancers, genetic disorders. • Some can be beneficial to the organism, then potentially beneficial to the species

Triploid • Mutation during meiosis when a complete set of chromosomes fails to separate • End up with a gamete that is 3 N (in trout normal 2 n = 58) • In Rainbow trout, this results in a sterile female that expends no energy producing eggs, trying to reproduce, etc. and can grow large • Many western state Game and Fish dept. are causing this mutation in eggs, to stock sterile fish

No energy expended to reproduce = more growth

http: //www. fishinglakes. com/Big Trout. htm

What is wrong with this image? 27. 5 lbs

45 lb King Salmon

DNA • http: //www. youtube. com/watch? v=gqv. YOr 78 THo&list=PLE 5692150 FBCABCB 1