Epidermal keratin messenger RNAs: A heterogeneous family

A messenger RNA fraction from guinea-pig skin sediments on sucrose gradients at approx. 19 S and codes for keratin polypeptides in a messenger-dependent reticulocyte lysate system. Partial purification of this fraction was achieved by two cycles of chromatography on oligo(dT)-cellulose, followed by two cycles of sucrose gradient centrifugation. The identities of the protein products as keratins were established by co-electrophoresis on sodium dodecyl sulfate-polyacrylamide gels, by peptide mapping, and by co-electrophoresis on two-dimensional polyacrylamide gels. All of the epidermal keratin polypeptides which are present in vivo are synthesized in vitro under the direction of this messenger. Fractionation of the messenger indicates that each different polypeptide is the product of a single mRNA species, and that no keratin is formed by proteolytic processing of higher molecular weight species or by polymerization of smaller precursors. Post-translational changes such as phosphorylation, which are known to occur in vivo, cannot be identified in the reticulocyte lysate system. Translation of these keratin messenger species is strongly inhibited by 7-methylguanosine 5′-triphosphate, indicating that the molecules have a ‘capped’ 5′-terminus.     

Ganglioside variations in amphibian brain tissue

Variation in the content and pattern of brain gangliosides from three anurans and two urodeles was analysed by thin-layer chromatography. The pattern for all three anurans was basically similar, though quantitative differences among species were detected. Ganglioside patterns from the two salamanders were distinctively different from that of the anurans and from one another, and more closely resembled the patterns seen in other tetrapods. Ganglioside variations in amphibians appear to reflect phylogenetic relationships better than life history or ecological factors.     

Identification of the coding region for the putidaredoxin reductase gene from the plasmid of Pseudomonas putida

The first 12 NH₂-terminal amino acids of the Pseudomonas putida putidaredoxin reductase were shown to be Met-Asn-Ala-Asn-Asp-Asn-Val-Val-Ile-Val-Gly-Thr. Comparison of these data with the DNA sequence of the BamHI-HindIII 197-base fragment derived from the PstI 2.2-kb fragment obtained from the P. putida plasmid showed that the putidaredoxin reductase gene was downstream from the cytochrome P-450 gene and the intergenic region had the 24-nucleotide sequence TAAACACATGGGAGTGCGTGCTAA. The Shine-Dalgarno sequence GGAG was detected in this region. The initiating triplet for the reductase gene was GTG, which normally codes for valine, but in the initiating codon position codes for methionine. From the amino acid sequence and X-ray data comparisons with other flavoproteins, what appears to be the AMP binding region of the FAD can be recognized in the NH₂-terminal portion of the reductase involving residues 5–35.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985.     

Wounding patterns in three species of captive macaques

The incidence of wounding in captive groups of rhesus (Macaca mulatta), pigtail (M. nemestrina), and stumptail (M. arctoides) macaques was studied for 21 months. Groups were monitored daily for evidence of wounding. Wounded animals were captured, treated by veterinary staff, and returned following recovery. Records were kept on the age, sex, and species of the recipient, along with the type and location of wound. In each species of macaque, adult males incurred the highest frequency of wounds and multiple wounds of any age-sex class. This contrasted with previously reported behavioral data indicating low frequencies of aggression received by adult males, especially contact aggression and bites. These discrepancies indicate wounding frequencies do not necessarily correspond with behavioral measures of aggression. Inhibition of aggression directed toward infants and the selective avoidance of bites directed to vital body regions were presented as possible mechanisms that modify intragroup aggression. Increased wounding in the birth season under captive conditions suggests that the pattern of increased wounding reported during the breeding season under freeranging conditions may reflect xenophobic responses to immigrating males, rather than direct male-male competition for estrous females.     

The effect of phenobarbital and 3′-methyl-N,N-dimethyl-4-aminoazobenzene administration on catalytic,binding and immunological properties of ligandin subunits in rat liver

Following administration of phenobarbital to rats, liver ligandin content, bilirubin binding, glutathione-S-transferase and steriod isomerase activities by 150% and the 22 000-dalton subunit was selectively increased. Following adminstration of 3′-methyl-N,N-dimethyl-4-aminoazobenzene, rat liver ligandin content and steroid isomerase decrased by 65%, glutathione-S-transferase incrased by 100%, bilirubin binding was abolished, and the relative proportion of the 22 000- and 25 000-dalton subunits remained unchanged.     

Effect on prescribing of the limited list in a computerised group practice.

The prescribing of drugs in the therapeutic classes that are affected by the government''s limited list was investigated in a computerised group practice of just over 3,000 patients. Prescribable drugs in categories that are affected by the list were identified for two consecutive six month periods before and one six month period after the introduction of the list. A significant decrease in the prescribing of cough and cold remedies, vitamins, and antacids occurred after the list was introduced, whereas no change occurred in the prescribing of laxatives, benzodiazepines, or analgesics. The prescribing of iron and penicillin increased significantly after the list was introduced, whereas the use of H2 antagonists and non-steroidal anti-inflammatory drugs showed no significant change.