Red Headed Stepchild
(The Barrett family memoir of Navy Life)
by Sophie Ruth Meranski with photos


p 103-1490 Wayne Daman jr pitched strongly in Forks High School shutout against Elma April 2001
Genetics Molecular Biology Word list [to be treated later] Cyclophilin A caveolae fision pore, lysosomes, histones, chromatin capsid apoptosis telomere chaperone ubiquitin Freund's adjuvant protease lac operon inosine aminoacyl-tRNA synthetase promoter [region of DNA] 5' untranslated regions of mRNA chemokines complement [immunologically active group of blod proteins] plasmids transposons major histocompatibilty complex immunoglobulins- heavy and light chains variable and constant regions antibodies cell-mediated immunity antigen-presenting cells dendritic and others macrophages monocytes 3' inititation-elongation-termination [of polypeptide synthesis] polyadenylation cistron, alternative splicing third-codon"wobble" (Francis Crick) reading frame Cells have an outside semipermeable double layered plasma membrane with two leaflets of glycolipid and phospholipid molecules. both contain cholesterol. the plasma membrane has a hydrophobic core. the outer layer has much phosphatidyl choline, sphingomyelin, and glycolipids - the inner phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol. Different viruses have found a variety of cellular receptors through which they can enter cells, often after using a docking mechanism. The carbohydrate sialic acid was one of the first cellular receptors discovered to permit entry of some virues. Influenza, and some rhinoviruses, Sendai virus, group A porcine rotavirus, and bovine parvovirus enter cells via the sialic acid receptor. Heparan sulfate is the receptor for Dengue fever, foot-and-mouth disease, and many herpesviruses. Vaccinia of the poxviruses may use heparan sulfate or epidermal growth factor receptor. HIV needs specialized receptors of CD4 lymphoid cells and macrophages. DOUBLE-STRANDED DNA contains the genetic information of cellular organisms prokaryotic bacteria and eukaryotic multicellular organisms, which usually have more than one chromosome and a nuclear membrane around the nucleus. Non-coding regions called INTRONS occur between sections of GENES called EXONS which encode PROTEINS. Three large molecules RNA POLYMERASES move along one strand of DNA from 3' to 5' end to transcribe genetic information from the DNA. POLYMERASE I forms the 18S RNA of the ribosome SMALL SUBUNIT and the 28 and 5.8 S RNAs of the ribosome LARGE SUBUNIT. These numbers refer to how these molecules move in ultracentrifuges, reflecting their sizes. POLYMERASE II transcribes MESSENGER RNA mRNA and the "small nuclear RNAs" snRNAs. Polymerase III transcribes 5 S RNA also in ribosome large subunit, and the 32 transfer RNAs, tRNAs, which have 73-93 nucleotides and have three looped structures, which attach specific amino acids at the 3' end. DNA is more stable than RNA because it mutates less and because there are several repair mechanisms in DNA. In DNA ADENINE A pairs with THYMINE T, whereas in RNA ADENINE pairs with URACIL U. In both DNA and RNA GUANINE G pairs with CYTOSINE C. rRNA and tRNA are housekeeping materials that occur in all cells, but Messenger RNAs are produced according to the needs of specific cells such as erthyrocytes that need hemoglobin, and so Messenger RNAs are produced when needed, as for instance on viral infection. Great precision is needed in splicing out non-coding regions, as a single missing or added codon [nucleotide] will throw off the reading of the triplet code by which proteins are designated. Spliceosomes containing several small nuclear RNAs snRNAs with proteins perform this function. An intron normally begins with codons GU snd ends with AG. ALTERNATIVE SPLICING permits a few genes to make a greater variety of PROTEINS. Messenger RNAs begin with a cap at the 5' end, and the normal signal to begin TRANSLATION is AUG, which encodes amino acid METHIONINE at the beginning of each protein chain. TRANSFER RNAs bring up the indicated amino acid during ELONGATION until a termination signal is reached. VIRUSES have developed diverse strategies to cause the cell's own ribosomal machinery to synthesize the proteins the virus needs for its reproduction and spread. Many viruses encode their genetic information in RNA - others DNA. The discovery of RNA viruses showed a very important exception to the rule observed in cellular organisms that information is stored in DNA and transcribed to RNA and translated to PROTEIN. A number of different classes of virus achieve this in different ways. By convention, mRNA is defined as positive + and many viruses have negative -minus strands. David Baltimore has designated six classes of viruses depending whether they have DNA or RNA and how many positive and negative strands. CLASS I contains DOUBLE STRAND DNA viruses - seven groups: There are five icosahedral shaped groups the circular Papovaviruses[simian virus 40], the linear Adenoviruses, both without envelopes and the enveloped circle-gapped Hepadnaviruses and linear Herpesviruses and the ctyoplasmic Iridoviruses - then Helical enveloped Baculoviruses and cytoplasmic enveloped complex-shaped Poxviruses - all with DNA. In the Baltimore classification Class III has two stranded RNA viruses, with one + and one - strand : the RNA is segmented with two RNA molecules in the BIRNAVIRUSES and ten-18 segments in the REOVIRUSES. Baltimore Class IV viruses have a SINGLE + strand of RNA which for replication generates a Negative strand -, which then creates a + mRNA - there are four types - the naked Icosahedral PICORNAVIRUSES include POLIOMYELITIS, foot-and-mouth disease, Encephalomyocarditis, Coxsackie, Echo- Entero- Hepatitis A and 91 types of Rhinoviruses - the last of nose colds. The CALICIVIRUSES reproduce similarly, as do the Enveloped FLAVIVIRUSES and TOGAVIRUSES [dengue fever, Sindbis, + Semliki forest viruses]. These groups have the RNA in a single molecule between 3.5 and 12 kilobases - relatively small. Baltimore class V viruses are enveloped and helical and have a single negative - RNA strand - six groups FILO- RHABDO- [rabies] BUNYA- ORTHOMYXO- [influenza A,B,C] PARAMYXO- [measles and Sendai] and BUNYA- VIRUSES. CLASS SIX are the RETROVIRUSES, which have two copies of a positive + RNA genome.These include Human Immunodeficiency virus HIV gibbon,age, murine, bovine, feline leukemia viruses, and Visna virus. ACYCLOVIR 9-(2-Hydroxymethyl) guanine Chian terminator; inhibits viral DNA replication vs HSV herpes simplex, VZV varicella-zoster AMANTADINE Tricyclo[3,3,1]dec-1-ylamine HCl Ion Channel blocker v. Influenza A virus FAMCICLOVIR 9-(4-Acetoxy-3-acetoxymethylbut-1-yl guanine Chain terminator inhibits viral DNA replication v. VSV FOSCARNET Trisodium phosphonoformate hexahydrate Noncompetitive inhibitor of viral DNA polymerase (pyrophosphate-binding site) v. HSV + other herpesviruses GANCICLOVIR 9-(1,3-Dihydroxy-2-propoxymethyl) guanine Competitive inhibitor of viral DNA polymerase v. HCMV human cytomegalovirus, HSV IDOXURIDINE 5-Iodo-2'-deoxyuridine and TRIFLUOROTHYMIDINE Disrupt transcription & translation after incorporation into viral DNA v. HSV RIBAVIRIN 1-b-D-Ribofuranoxyl-1,2,4 triazole 3-carboxamide unclear mechanism v. RSV respiratory syncytial virus VIDARABINE 9-b-D-Arabinofuranoxyl adenine monohydrate DNA synthesis inhibitor mechanism unknown v. HSV, VZV Study of viral life cycles is likely to show ways to disrupt their penetration of cell membranes through specific types of receptors and their transport to cell nuclei and ribosomes where many operate. Some use clathrin coated pits by pinocytosis - others utilize first early endosomes in outer cell layers and then late endosomes nearer the nuclear membranes or envelope - texts use different terminology.
Year: 2001