Ersfeld K, Gull K
University of Manchester, School of Biological Sciences, 2.205 Stopford Building, Oxford Road, Manchester M13 9PT, UK.
Science. 1997 Apr 25;276(5312):611-4. doi: 10.1126/science.276.5312.611.
The Trypanosoma brucei nuclear genome contains about 100 minichromosomes of between 50 to 150 kilobases and about 20 chromosomes of 0.2 to 6 megabase pairs. Minichromosomes contain nontranscribed copies of variant surface glycoprotein (VSG) genes and are thought to expand the VSG gene pool. Varying VSG expression allows the parasite to avoid elimination by the host immune system. The mechanism of inheritance of T. brucei chromosomes was investigated by in situ hybridization in combination with immunofluorescence. The minichromosome population segregated with precision, by association with the central intranuclear mitotic spindle. However, their positional dynamics differed from that of the large chromosomes, which were partitioned by kinetochore microtubules.
布氏锥虫的核基因组包含约100条大小在50至150千碱基之间的微型染色体和约20条大小在0.2至6兆碱基对之间的染色体。微型染色体包含可变表面糖蛋白（VSG）基因的非转录拷贝，被认为可扩大VSG基因库。VSG表达的变化使寄生虫能够避免被宿主免疫系统清除。通过原位杂交结合免疫荧光技术研究了布氏锥虫染色体的遗传机制。微型染色体群体通过与核内中央有丝分裂纺锤体结合而精确分离。然而，它们的位置动态与大染色体不同，大染色体是由动粒微管进行分配的。
