From monoclonal antibody to gene for a neuron-specific glycoprotein in Drosophila

A monoclonal antibody (MAb24B10), derived from mice immunized with Drosophila retina, exclusively stains photoreceptor cells in the retina and their axonal projections to the optic ganglia. The antigen (Ag24B10) is a 160-kDa glycoprotein comprising about 0.8% of the retina protein. By microsequencing, 19 of the first 21 amino acids at the NH2-terminal end of the protein have been determined. Using synthetic oligonucleotide probes corresponding to a portion of this amino acid sequence, we isolated a homologous genomic clone. A partial DNA sequence of this clone, along with blot experiments on genomic DNA and RNA, indicate that this clone is part of the structural gene for Ag24B10. By in situ hybridization, the gene was localized to the tip of chromosome 3R

Effect of aerial O-2 partial pressure on bimodal gas exchange and air-breathing behaviour in Trichogaster leeri

© The Company of Biologists Ltd 2007The effects of experimental alterations of aerial O2 partial pressure (PO2,air) on bimodal gas exchange and airbreathing behaviour were investigated in the aquatic airbreathing fish Trichogaster leeri in normoxic water. Fish responded to increasing PO2,air by decreasing air-breathing frequency, increasing aerial O2 consumption rate (VO2),increasing mean O2 uptake per breath (VO2/breath) and decreasing aquatic VO2 to maintain a constant total VO2. The rate of oxygen uptake from the air-breathing organ (ABO) during apnoea (VO2,ap) was derived on a breath-bybreath basis from VO2/breath and apnoea duration. VO2,ap and estimates of ABO volume were used to calculate the PO2 in the ABO at the end of apnoea. This increased with increasing PO2,air, suggesting that ABO-PO2 is not regulated at a constant level by internal chemoreceptors. Furthermore, mean VO2,ap increased with increasing PO2,air, indicating that the observed increase in VO2/breath with increasing PO2,air was facilitated not only by an increase in apnoea duration but also by an increase in the air–blood PO2 gradient.Lesley A. Alton, Craig R. White and Roger S. Seymou

Computational challenges of systems biology

Progress in the study of biological systems such as the heart, brain, and liver will require computer scientists to work closely with life scientists and mathematicians. Computer science will play a key role in shaping the new discipline of systems biology and addressing the significant computational challenges it poses