[
Cell Death and Differentiation,
2004]
The award of the 2002 Nobel Prize to Brenner, Sulston, and Horvitz was one of the most satisfying I can recall, recognizing as it did the long sought meaningful conjunction of developmental biology with cancer research. Cancer is the ultimate derangement of growth and differentiation, affecting as it does the placenta, the embryo, the fetus, the infant, the child, the adolescent, and the adult of any age. Little wonder then that developmental biologists (embryologists in bygone days) have contributed so much to our understanding of cancer's origin. Indeed, the first coherent view of cancer was painted by the great embryologist Theodor Boveri in his heuristic volume of 1914 on the origin of cancer. Having observed the developmental aberrations of sea urchin embryos that can follow upon abnormalities of centrosome number and of the segregation of chromosomes, he associated causally the already known phenomenon of centrosome abnormalities of cancer with the latter's histopathology. He further posited that such pathology could be attributed to a single chromosomally aberrant cell.
[
Neurodegener Dis,
2007]
Parkinson''s disease (PD) is one of the most common age-related neurodegenerative diseases that is characterized by selective loss of dopaminergic neurons. Despite recent findings from mammalian model systems, molecular mechanisms of the pathophysiology are poorly understood. Given the high conservation of molecular pathways from invertebrates to mammalians, combined with technical advantages, such as high-throughput approaches, Caenorhabditis elegans represents a powerful system for the identification of factors involved in neurodegeneration. In this review we describe that C. elegans can be used to advance our understanding of the genetic mechanisms implicated in these disorders. Copyright (c) 2007 S. Karger AG, Basel.
[
Int J Parasitol,
2000]
Onchocerca volvulus, the filarial parasite that causes onchocerciasis or river blindness, contains three distinct genomes. These include the nuclear genome, the mitochondrial genome and the genome of an intracellular endosymbiont of the genus Wolbachia. The nuclear genome is roughly 1.5x10(8) bp in size, and is arranged on four chromosome pairs. Analysis of expressed sequence tags from different life-cycle stages has resulted in the identification of transcripts from roughly 4000 O. volvulus genes. Several of these transcripts are highly abundant, including those encoding collagen and cuticular proteins. Analysis of several gene sequences from O. volvulus suggests that the nuclear genes of O. volvulus are relatively compact and are interrupted relatively frequently by small introns. The intron-exon boundaries of these genes generally follow the GU-AG rule characteristic of the splice donor and acceptors of other vertebrate organisms. The nuclear genome also contains at least one repeated sequence family of a 150 bp repeat which is arranged in tandem arrays and appears subject to concerted evolution. The mitochondrial genome of O. volvulus is remarkably compact, only 13747 bp in size. Consistent with the small size of the genome, four gene pairs overlap, eight contain no intergenic regions and the remaining gene pairs are separated by small intergenic domains ranging from 1 to 46 bp. The protein-coding genes of the O. volvulus mitochondrial genome exhibit a striking codon bias, with 15/20 amino acids having a single codon preference greater than 70%. Intraspecific variation in both the nuclear and mitochondrial genomes appears to be quite limited, consistent with the hypothesis that O. volvulus has suffered a genetic bottleneck in the recent past.