An investigation of potential vascular connections between the kidney and the adrenal gland

This study was conducted on two species of monkeys, Macaca fascicularis and Macaca mulatta, to determine if there were vascular connections between the kidney and other abdominal structures such as the adrenal glands. Microfil vascular perfusions, followed by microscopic observations and dissections, were utilized to investigate the existence of these potential connections. Highly anastomotic renal capsular vessels were always observed on the outer surface of the renal capsule. However, these capsular vessels did not make connections with the subcapsular capillary plexus in the majority of monkeys studied. Vascular connections between the adrenal gland and kidney were not observed. It was concluded that, although the region between the adrenal gland and kidney was rich in vasculature, it did not appear to play an anatomical role in anastomosing the extrarenal and intrarenal circulations.     

Amino acid replacements resulting from super-suppression of nonsense mutants of iso-1-cytochrome c from yeast

The eight class I, set 1 super-suppressor genes, SUP2, SUP3, SUP4, SUP5, SUP6, SUP7, SUP8 and SUP11 are not closely linked and map at distinct loci throughout the genome of yeast. Each of these suppressors causes the production of 5 to 10% of the normal amount of iso-1-cytochrome c when it is individually coupled to the ochre (UAA) mutant cy1-2. All eight iso-1-cytochromes c contain a residue of tyrosine at position 20 which corresponds to the site of the ochre codon. Several of these super-suppressors also were shown to act on cy1-9, but at a much lower efficiency. It was shown that iso-1-cytochrome c from one of the suppressed cy1-9 strains contains a tyrosine at position 2, which corresponds to the site of the ochre codon in this mutant. It is suggested that the gene product of the eight super-suppressors is tyrosine transfer RNA.     

The protein translocation machinery of the endoplasmic reticulum

The rough endoplasmic reticulum (r.e.r.) has been postulated to possess a single translation-coupled translocation system (in multiple copies) that effects signal sequence-mediated translocation of all secretory and lysosomal proteins and integration of all integral membrane proteins whose port of entry is the rough endoplasmic reticulum (G. Blobel 1980 Proc. natn. Acad. Sci. U.S.A. 77, 1496-1500). Two proteins have been isolated that are components of the r.e.r. translocation system. Their properties and function in protein translocation across and integration into membranes are discussed.