Amino acid sequences of seven Vβ, eight Vα, and thirteen Jα novel human TCR genes

The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L06866-L06893.     

S-100 protein-induced changes in the physical state of synaptosomal particulate fractions as monitored by spin labels

This report documents changes in the physical state of synaptosomal particulate fractions (SYN) upon binding of S-100 protein, as monitored by spin labels. Studies were conducted on SYN labeled with either 5-doxylstearic acid or 16-doxylstearic acid, which probe the polar region and the hydrophobic core of the lipid bilayer, respectively. S-100 perturbs to some extent both the polar surface and the hydrophobic core of SYN in a time- and temperature-dependent manner. Ca2+ is essential for S-100 to perturb the membranes. K+ almost completely inhibits the S-100 perturbing effect if present in the incubation medium, but fails to reverse the S-100-induced changes if added after S-100 has interacted with SYN. At room temperature and below, the overall S-100 effect registered after about 30 min of association of the protein with SYN is an increase in the fluidity of both the surface and the interior of the membranes. Spectra registered at intervals at room temperature indicate that the S-100 perturbing effect on the membrane surface is practically monophasic, consisting of an increase in fluidity, while that on the membrane interior is multiphasic, consisting of a decrease in fluidity during the first 10 min of association, followed by an increase in fluidity during the subsequent 20 min and a return to starting values during the second 30 min of association. Around 37 degrees C, on the contrary, a decrease in fluidity is registered in both regions. The data suggest that S-100 induces a spatial rearrangement of membrane components (proteins) involved in the specific binding and/or partially penetrates into the lipid bilayer.     

The case for studying tadpole autecology,with comments on strategies to study other small,fast-moving animals in nature

Two of the most fundamental questions in tadpole biology, also applicable to most small, under-studied organisms are: (1) ‘Why are they built the way they are?’ and (2) ‘Why do they live where they do?’ Regrettably, despite significant progress in most aspects of tadpole biology, the answers to these questions are not much better now than they were in the last century. We propose that an autecological approach, that is the careful observation of individuals and how they interact with the environment, is a potential path towards a fuller understanding of tadpole ecomorphology and evolution. We also discuss why more attention should be given to studying atypical tadpoles from atypical environments, such as torrential streams, water-filled cavities of terrestrial plants and wet rock surfaces neighbouring streams. Granted, tadpoles are rare in these settings, but in those unusual habitats the physical environments can be well described and characterized. In contrast, the more common ponds where tadpoles are found are typically too structurally complex to be easily delineated. This makes it difficult to know exactly what individual tadpoles are doing and what environmental parameters they are responding to. Our overall thesis is that to understand tadpoles we must see exactly what they are doing, where they are doing it, and how they are doing it. This takes work, but we suggest it is feasible and could greatly advance our understanding of how anuran larvae have evolved. The same strategies for studying tadpoles that we encourage here can be applied to the study of many other small and fast-moving animals.