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Chromatin Structure Overview to Histone Deacetylation6Topics
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Nucleoside and Nucleotide Basics to Base Pairing and DNA Stability5Topics
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Introduction to Nucleotide Synthesis Inhibition to Broad-Spectrum Inhibitors and CPS Enzymes5Topics
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Purine Metabolism and Salvage Pathways to Genetic Code: Commaless and Universal6Topics
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DNA Replication Basics to Detailed Lagging Strand Synthesis7Topics
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DNA Repair: Nonhomologous End Joining to DNA Repair: Mismatch Repair5Topics
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Introns vs Exons: Basic Definitions to Visualizing Alternative Splicing and Protein Diversity4Topics
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tRNA Structure Overview to mRNA Stop Codons6Topics
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Introduction to DNA Mutations to Lac Operon Gene Expression States8Topics
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Cilia Structure: Motile Cilia and Basal Body to K+ Pump Inhibition6Topics
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Page 1 — Eukaryotic Gene Overview to Page 1 — RNA Processing: Splicing & Fate8Topics
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Osteogenesis Imperfecta: Genetic Basis to Menkes Disease6Topics
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Eukaryotic RNA Polymerases: Types to Splicing Diagram: Lariat & Mature mRNA7Topics
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Flow Cytometry: Basics and Applications to ELISA: Principle and Uses4Topics
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Protein Synthesis: Initiation Phase to Posttranslational Modifications: Chaperone Proteins6Topics
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Karyotyping: Principles and Applications to Molecular Cloning: Process and Applications4Topics
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Cell Cycle Phases and Regulation to p53 and Apoptosis Induction7Topics
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Introduction to Imprinting Disorders to Visualizing Normal vs. Mutated Chromosomes6Topics
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Rough Endoplasmic Reticulum Functions to Specific Vesicular Trafficking Proteins7Topics
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Autosomal Dominant Inheritance to Pedigree Chart Symbols6Topics
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Peroxisome Functions to Drugs Affecting Microtubules5Topics
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Polyunsaturated Essential Fatty Acids to Water-Soluble Vitamins: Deficiencies and Coenzyme Functions5Topics
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Collagen Introduction and Type I to Collagen Synthesis: Maturation and Fibril Formation6Topics
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Vitamin B7 (Biotin): Function and Deficiency to Vitamin B9 (Folate): Deficiency, Causes, and Prevention3Topics
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Elastin: Structure and Composition to PCR Cycle: Elongation and Repetition8Topics
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Ethanol Metabolism Overview to Pharmacological Interventions in Alcohol Metabolism5Topics
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CRISPR to Interpreting Southern Blot Results5Topics
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Key Metabolic Locations to Glucose Breakdown and NADPH Production4Topics
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Transgenic Strategies in Mice to Epistasis and Aneuploidy7Topics
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Pyruvate Dehydrogenase Deficiency to The TCA Cycle (Krebs Cycle)3Topics
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Genetic Terms: Dominant Negative & Linkage Disequilibrium to Conditions for Hardy-Weinberg Equilibrium7Topics
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ETC Overview to Fatty Acids in Gluconeogenesis9Topics
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Autosomal Dominant Disorders to CFTR Channel Function Diagram11Topics
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Phenylketonuria: Basic Defect and BH4 Deficiency to Alkaptonuria7Topics
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X-linked Recessive Diseases Introduction to Myotonic Dystrophy6Topics
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Fatty Acid Synthesis Overview to Medium-Chain Acyl-CoA Dehydrogenase Deficiency4Topics
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Mitochondrial Diseases: MELAS & MERRF to Trinucleotide Repeat Diseases: Fragile X & Friedreich Ataxia8Topics
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Hepatic Ketone Body Synthesis to Adipocyte Metabolism: Fed State4Topics
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Autosomal Trisomies & Down Syndrome Overview to Second Trimester Screening & NIPT8Topics
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Metabolic Fuel Use: Initial Exercise to Starvation After Day 3 and Stored Energy Depletion7Topics
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Genetic Disorders: Chromosomes 3-7 to Williams Syndrome6Topics
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Dietary Lipid Absorption and Chylomicron Entry to IDL, LDL Formation, and Uptake4Topics
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Vitamin A: Functions and Forms to Vitamin B1: Beriberi Forms7Topics
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Vitamin B2: Function and Deficiency to Vitamin B6 Deficiency Symptoms7Topics
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Vitamin B12: Name, Function, and Sources to Vitamin C: Excess and Toxicity7Topics
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Vitamin D Introduction and Function to Vitamin E Deficiency and Excess Effects6Topics
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Vitamin K Function to Marasmus: Characteristics and Visuals7Topics
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Enzyme Terminology: Kinase & Phosphorylase to Rate-Determining Enzymes: Lipid Metabolism7Topics
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ATP Production Pathways to Hexokinase vs Glucokinase: Kinetics & Regulation5Topics
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Glycolysis Net Reaction to PDC: α-Ketoglutarate & Arsenic7Topics
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Introduction to Pentose Phosphate Pathway to G6PD Deficiency: Biochemical Mechanism of Oxidative Stress7Topics
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Essential Fructosuria to Galactose Metabolism Pathway & Summary6Topics
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Sorbitol Pathway and Diabetic Complications to Acidic and Basic Amino Acids6Topics
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Urea Cycle Introduction to Hyperammonemia Treatment5Topics
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Ornithine Transcarbamylase Deficiency to Catecholamine Synthesis and Degradation5Topics
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Homocystinuria: Genetic Causes to Methylmalonic Acidemia: Deficiency & Metabolism6Topics
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Glucagon to Glycogen Disorders and Enzymes6Topics
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Introduction to Glycogen Storage Diseases to McArdle Disease (Type V)6Topics
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Lysosomal Storage Diseases Intro & Tay-Sachs to Lysosomal Storage Disease Pathway6Topics
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Key Enzymes in Lipid Transport - Part 1 to Major Apolipoproteins - Part 25Topics
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Lipoprotein Functions: Chylomicron & VLDL to Familial Dyslipidemias: Dysbetalipoproteinemia & Hypertriglyceridemia5Topics
Protein Synthesis: Initiation Phase to Posttranslational Modifications: Chaperone Proteins
Content August 26, 2025
Protein synthesis
Initiation
- Eukaryotic initiation factors (eIFs) identify the 5′ cap.
- eIFs help assemble the 40S ribosomal subunit with the initiator tRNA.
- eIFs released when the mRNA and the ribosomal 60S subunit assemble with the complex. Requires GTP.
Eukaryotes: 40S + 60S → 80S (even).
Prokaryotes: 30S + 50S → 70S (prime).
Synthesis occurs from N-terminus to C-terminus.
ATP-tRNA Activation (charging).
GTP-tRNA Gripping and Going places (translocation).
Elongation
- Aminoacyl-tRNA binds to A site (except for initiator methionine, which binds the P site), requires an elongation factor and GTP.
- rRNA (“ribozyme”) catalyzes peptide bond formation, transfers growing polypeptide to amino acid in A site.
- Ribosome advances 3 nucleotides toward 3′ end of mRNA, moving peptidyl tRNA to P site (translocation).
Think of “going APE“:
A site = incoming Aminoacyl-tRNA
P site = accommodates growing Peptide
E site = holds Empty tRNA as it Exits
Elongation factors are targets of bacterial toxins (eg, Diphtheria, Pseudomonas).
Termination
Eukaryotic release factors (eRFs) recognize the stop codon and halt translation → completed polypeptide is released from ribosome. Requires GTP.
Shine-Dalgarno sequence – ribosomal binding site in prokaryotic mRNA. Recognized by 16S RNA in ribosomal subunit. Enables protein synthesis initiation by aligning ribosome with start codon so that code is read correctly.
Protein synthesis
#boundingbox
This diagram illustrates the complete process of protein synthesis, from initiation to termination.
Posttranslational modifications
Trimming
Removal of N- or C-terminal propeptides from zymogen to generate mature protein (eg, trypsinogen to trypsin).
Covalent alterations
Phosphorylation, glycosylation, hydroxylation, methylation, acetylation, and ubiquitination.
Chaperone protein
Intracellular protein involved in facilitating and maintaining protein folding. In yeast, heat shock proteins (eg, HSP60) are constitutively expressed, but expression may increase with high temperatures, acidic pH, and hypoxia to prevent protein denaturing/misfolding.
Topics Covered:
- Protein Synthesis: Initiation Phase
- Protein Synthesis: Elongation Phase
- Protein Synthesis: Termination and Prokaryotic Initiation
- Visualizing Protein Synthesis
- Posttranslational Modifications: Trimming and Covalent Changes
- Posttranslational Modifications: Chaperone Proteins
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