Birago C, Bucci A, Dore E, Frontali C, Zenobi P
Mol Biochem Parasitol. 1982 Jul;6(1):1-12. doi: 10.1016/0166-6851(82)90048-2.
A strain of Plasmodium berghei (NK 65) was followed during syringe transmission in mice for over 120 passages after the last complete cycle, while the following parameters were monitored: (a) capacity to infect mosquitoes, inducing oocyst formation; (b) presence in the peripheral blood of morphologically identifiable gametocytes; (c) presence of a repetitive component in the DNA extracted from intraerythrocytic population. The suggestion of a possible role of this component in gametogenesis came from an earlier work (Dore, E., Birago, C., Frontali, C. and Battaglia, P.A. (1980) Mol. Biochem. Parasitol. 1, 199-208). Present results confirm the correlation between proportion of repetitive DNA and infectivity towards mosquitoes with a correlation coefficient r = 0.92-0.07+0.04. A parallel decrease of the two quantities is observed in the course of syringe transmission. A limited number of cloned lines, derived from strain NK 65 at different times during syringe transmission, shared the infectivity properties of the parent strain at the moment of cloning, thus confirming that in the infective stage single asexual parasites from the schizogonic cycle are able to originate the whole cycle. The above arguments and results suggest that differentiation into active gametocytes involves amplification of a portion of the genome.
在小鼠体内通过注射器传代对伯氏疟原虫（NK 65株）进行跟踪研究，在最后一个完整周期后传代超过120次，同时监测以下参数：（a）感染蚊子并诱导卵囊形成的能力；（b）外周血中形态可识别的配子体的存在情况；（c）从红细胞内群体中提取的DNA中重复成分的存在情况。该成分在配子发生中可能发挥作用的推测源于早期的一项研究（Dore, E., Birago, C., Frontali, C.和Battaglia, P.A.（1980年）《分子生物化学寄生虫学》1, 199 - 208）。目前的结果证实了重复DNA比例与对蚊子的感染性之间的相关性，相关系数r = 0.92 - 0.07 + 0.04。在注射器传代过程中观察到这两个量平行下降。在注射器传代的不同时间从NK 65株衍生出的有限数量的克隆系，在克隆时具有亲代菌株的感染特性，从而证实了在感染阶段来自裂殖生殖周期的单个无性寄生虫能够引发整个周期。上述论点和结果表明，向活跃配子体的分化涉及基因组一部分的扩增。
