from gene to protein. proteins review accomplish most of the major cellular functions enzymes –...
TRANSCRIPT
From Gene to Protein
Proteins Review Accomplish most of the major cellular
functions Enzymes – catalyze reaction Structural fibers (cytoskeleton, muscle fibers etc.) Materials transport (hemoglobin carries oxygen,
carrier proteins or channels in cell membranes etc.)
Hormones or signals (insulin etc.) Pigments provide colors (chlorophyll, melanin) Immune function (antibodies)
Protein Structure Sequence of amino
acids Only 20 possibilities
The sequence is determined by genes (DNA)
Different proteins have different sequences and thus fold into very different 3-d shapes
From Gene to Protein DNA is transcribed
into RNA in the nucleus
RNA carries the code to ribosomes where the code is translated into a protein (polypeptide)
Where Ribosomes Are
Either in the cytosol (fluid of the cell) Makes proteins for inside the cell
Or attached to the rough endoplasmic reticulum Makes proteins to be shipped
Ribosomes in the Rough ER
Make proteins which then get wrapped in a membrane made by the ER
Known as a vesicle
Can be transported andkept separate from thecytosol
The Function of the Golgi
Vesicles from the ER usually go to the Golgi
Can be modified, tagged, sorted and shipped to a new location
Final Destination Vesicle can take protein to any
organelle or can form new organelle like a lysosome or vacuole
Can take protein to a membrane (organelle or plasma membrane)
Can expel protein outside of cell (i.e. into blood stream)
Chloroplast and Mitochondria Are thought to have once been free-living bacteria
Somehow got taken in by a cell and began living with it, eventually becoming a part of
Called endosymbiosis
So they make someof their ownproteins
Most genes haverelocated to nucleus
Evidence for Endosymbiosis
Chloroplasts and mitochondria are similar size to most bacteria
Contain their own DNA which has a similar structure to bacterial DNA
Contain their own ribosomes similar to bacterial ribosomes
Reproduce similarly to bacteria
Main Point
Genes code for traits by coding for proteins which have functions throughout the cell
Proteins go to different organelles and accomplish most functions of the cell
Cell Animation
http://www.youtube.com/watch?v=yKW4F0Nu-UY
Way more in depth- made for Med School students – but helps visualize dynamic nature of cell and see some major organelles/activities
R.A.F.T. Assignment - Individual Role: Functional protein
Audience: A newly made protein either in an organelle or in the blood
Format: A written method of your choice (story, poem, song, cartoon etc.)
Topic: “The Talk” – telling the protein where it came from and how it got there.