褐飞虱若虫中肠凋亡细胞的检测

Detection of midgut apoptosis in Nilaparvata lugens larvae

为揭示褐飞虱Niloparvata lugens Stl若虫在发育过程中中肠的凋亡细胞,使用末端脱氧核苷酸转移酶介导的dUTP-生物素断端标记法(TUNEL)进行中肠组织切片检测,结果表明,1～5龄若虫中肠分别存在2%～5%的凋亡细胞。利用4′,6-二脒基-2-苯基吲哚二盐酸(DAPI)染色法检测表明,存在Ⅰ,Ⅱa和Ⅱb期凋亡的细胞核,其特征包括染色体浓缩、边缘化及细胞核碎裂。透射电子显微镜检测结果表明,早期凋亡的细胞呈现染色质浓缩、边缘化特征,晚期凋亡的细胞出现细胞核碎裂、形成凋亡小体及细胞质空泡化等。本研究揭示了在正常发育过程中褐飞虱若虫中肠有少量的细胞发生了凋亡。通过人工干预的方式调控中肠细胞的凋亡进程有可能使之成为防治该水稻害虫的新靶标。

Midgut apoptosis was investigated in the brown planthopper（Nilaparvata lugens Stl,Hemiptera：Delphacidae） larvae.A terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling（TUNEL） assay revealed that two to five percent of the 1st -5th larval instar midgut cells showed typical fluorescent signals representing genomic DNA cleavage.4＇,6 -diamidino-2-phenylindole（DAPI） staining revealed apoptotic nuclei presenting characteristic features in apoptosis stage Ⅰ,Ⅱ a and Ⅱ b;including chromatin condensation,margination and nuclear fragmentation.Transmission electron microscopy revealed that early stage apoptotic midgut cells had apoptotic nuclear morphology,such as chromatin condensation and margination,while late stage cells had broken nuclei,apoptotic bodies and vacuolization of the cytoplasm.These findings demonstrate that a small percentage of the midgut cells of N.lugens larvae undergo apoptosis during normal development.It may be possible to regulate N.lugens midgut apoptosis artificially thereby making this process a novel method of control for this species.