Biology Partnership (A Teacher Quality Grant) RNA and Protein Synthesis Nancy Dow Jill Hansen Tammy Stundon October 20, 2012 Gulf Coast State College Panhandle Area Educational Consortium 5230 West Highway 98 753 West Boulevard Panama City, Florida 32401 Chipley, Florida 32428 850-769-1551 877-873-7232 www.gulfcoast.edu Pre-test Q and A board What is RNA How do we use RNA? What are the different forms of RNA? How do we produce an actual human from just a series of letters?? Florida Next Generation Sunshine State Standards SC.912.L.16.3 Describe the basic process of DNA replication and how it relates to the transmission and conservation of the genetic information. Also Assesses SC.912.L.16.4 Explain how mutations in the DNA sequence may or may not result in phenotypic change. Explain how mutations in gametes may result in phenotypic changes in offspring. SC.912.L.16.5 Explain the basic processes of transcription and translation, and how they result in the expression of genes. SC.912.L.16.9 Explain how and why the genetic code is universal and is common to almost all organisms Florida Next Generation Sunshine State Standards Benchmark Clarifications • Students will describe the process of DNA replication and/or its role in the transmission and conservation of genetic information. • Students will describe gene and chromosomal mutations in the DNA • sequence. • Students will explain how gene and chromosomal mutations may or may not result in a phenotypic change. • Students will explain the basic processes of transcription and/or translation, and their roles in the expression of genes. • Students will explain that the basic components of DNA are universal in organisms. • Students will explain how similarities in the genetic codes of organisms are due to common ancestry and the process of inheritance. Florida Next Generation Sunshine State Standards Content Limits • Items requiring the analysis of base pairs for gene mutations are limited to changes in a single gene. • Items may refer to but will not assess the cell cycle, mitosis, and/or meiosis. • Items will not require memorization of specific conditions resulting from chromosomal mutations. • Items may refer to the process of meiosis in the context of mutations but will not assess meiosis in isolation. • Items addressing transcription or translation will not require specific knowledge of initiation, elongation, or termination Blame it on the DNA Structure of DNA DNA is made of subunits called nucleotides DNA nucleotides are composed of a phosphate, deoxyribose sugar, and a nitrogencontaining base The 4 bases in DNA are: adenine (A), thymine (T), guanine (G), and cytosine (C) Remember Replication? 8 Hold up, wait a minute…. • DNA is only found in the nucleus • Who we are, how we look, and the mechanisms that make our body function are all determined by proteins • Proteins are only made in the ribosome.. Why do we need both DNA and RNA? • DNA holds all the genetic information • DNA damage = mutation • Safer in the nucleus • RNA acts as messenger Why do we need both DNA and RNA? Central Dogma holds that genetic information is expressed in a specific order. This order is as follows Central Dogma Video DNA vs RNA Sugar Bases Strand DNA vs RNA Types of RNA RNA Foldable 2 Types of RNA 1 2 3 1 3 . Three Types of RNA 1. Messenger RNA (mRNA) copies DNA’s code & carries the genetic information to the ribosomes 2. Ribosomal RNA (rRNA), along with protein, makes up the ribosomes 3. Transfer RNA (tRNA) transfers amino acids to the ribosomes where proteins are synthesized Protein Synthesis: Step 1 DNA unwinds and mRNA is made complementary to the DNA A=U G=C Transcription –the making of messenger RNA (mRNA) from DNA in the nucleus 3 nitrogen bases in mRNA is called a codon Protein Synthesis: Step 1 Where to start? 1. DNA unzips along hydrogen bonds 2. Free RNA nucleotides pair with the complementary DNA bases (C-G and U-A) along the exposed DNA strand forming an RNA transcript 3. RNA transcript released from the DNA 4. DNA closes again Protein Synthesis: Step 1 The transfer of information in the nucleus from a DNA molecule to an RNA molecule • Only 1 DNA strand serves as template • Starts at promoter DNA (TATA) • Ends at terminator (AAAAA) • When complete, preRNA molecule is released Protein Synthesis: Step 1 ½ Not all the RNA codes for something! • A specialized nucleotide is added to the beginning of each mRNA molecule which forms a cap. It helps the mRNA strand bind to a ribosome and prevents the strand from being broken down too fast. • The end of the mRNA molecule gets a string of AAAA nucleotides (poly A tail) that helps the mRNA molecule exit the nucleus. • The extra footage takes the form of nucleotide segments that are not included in the final protein. Cleaning Up the Message • Contains unwanted bases • The ‘junk’ sequences (called introns) are removed from the message and the remaining sequences (exons) are linked together to produce a sequence of codons that will translate into a polypeptide. • This process occurs before the message leaves the nucleus. Protein Synthesis: Step 1 ½ There’s Junk in My DNA! Final processing of the mRNA includes removal of introns, leaving the exons to direct protein synthesis Let’s Catch Up DNA Codes for RNA, Which Codes for Protein The Language of Proteins • Each 3 nucleotide sequence in an mRNA strand is called a codon. • Each codon codes for a 1 amino acid. • The codon sequence codes for an amino acid using specific rules. These specific codon/amino acid pairings is called the Genetic Code. The Language of Proteins • There are 64 (43) possible codes, but only 20 amino acids. • More than 1 triplet may code for the same amino acid. This is fine as long as no triplet can code for more than one a.acid. • Note that several codons can also act as start (AUG) or stop (UAA) signals. Toss the Ball Review The Genetic Code Codon Music Time to Practice! Mutations • Mutation: change in DNA • If a base is substituted or deleted, the triplet(s) are different • This sometimes leads to difference in the protein Putting it All Together Putting it All Together 1) rRNA (ribosomal RNA) attaches to mRNA and starts reading the codons 2) tRNA (transfer RNA) – carries amino acids and attaches them to the growing protein chain 3) When protein production is complete, the ribosome releases the protein chain Putting it All Together Structure • Two subunits, each composed of ribosomal RNA (rRNA) and protein Function • Bring tRNA bearing an amino acid close enough to mRNA to interact – Permit alignment of anticodon and codon DNA Codes for RNA, Which Codes for Protein Transcription Translation 39 Scavenger hunt Follow Up Q/A board Post Test UAG Try It - Simulations Cool Stuff Awesome Scarf Genome Quilts From Gamer to Scientist Some Other Goodies •• Trippy Protein Synthesis Dance Dance Trippy Protein Synthesis • http://www.youtube.com/watch?v=gqvYOr78THo (Blame it on the • Tik DNA)Tok (Protein Synthesis) •• http://www.youtube.com/watch?v=_Q2Ba2cFAew&feature=related Translation Mario Style (Central dogma) •• The Cell Will Survive (Sing Along) http://www.youtube.com/watch?v=bpMhgAGybe4 •• http://www.youtube.com/watch?v=ZPlnDzkBrpc (mario translation) Genetic Music • http://www.youtube.com/watch?v=5ldkJxCzXak (sing along)? •• DNA Song http://www.youtube.com/watch?v=tQv5Ho8zsKI codon bell ringer • DNA, Hotpockets, and the Longest Word Ever • http://www.youtube.com/watch?v=tVrkBJz9q0g Born to be wildtype (bad singing)