Singh A K, Lakhotia S C
Department of Zoology, Kuteer Post-Graduate College, Chakkey, Jaunpur, India.
Cell Stress Chaperones. 2000 Apr;5(2):90-7. doi: 10.1379/1466-1268(2000)005<0090:tsviti>2.0.co;2.
The patterns of heat-induced synthesis (37 degrees C to 45 degrees C) of heat shock proteins (Hsps) in different tissues of grasshoppers and cockroaches from natural populations and in laboratory-reared gram-pest (Heliothis armigera) were examined by 35S-methionine labeling and sodium dodecyl sulfate-polyacrylamide gel electrophoresis fluorography. Whereas 45 degrees C was lethal in most cases, optimal induction of Hsp synthesis was seen between 37 degrees C and 42 degrees C. The ongoing protein synthesis was not much affected at these temperatures, except in the tissues of adult H. armigera exposed to 42 degrees C. The profiles of the Hsps induced in the tissues of the insects, however, were different. From the relative abundance of the synthesis of 70-kDa (Hsp70) and 64-kDa (Hsp64) polypeptides, three categories of heat shock response were identified: (1) induction of abundant Hsp70 but little Hsp64 (malpighian tubules, male accessory glands, and ovaries of adult grasshoppers), (2) abundant Hsp64 but little Hsp70 (testes of adult grasshoppers, testes and malpighian tubules of adult cockroaches, and testes, malpighian tubules, and fat bodies of H. armigera larvae), and (3) induction of both Hsp70 and Hsp64 in more or less equal abundance (ovaries of adult cockroaches, salivary glands of H. armigera larvae, and malpighian tubules, male accessory glands, testes, and ovaries of adult H. armigera). Cockroaches collected from storerooms showed detectable synthesis of Hsp64 and/or Hsp70 only after heat shock, but those collected from drains showed detectable synthesis of both Hsp70 and Hsp64 in different tissues without heat stress. Western blotting showed that the 64-kDa polypeptide in these insects is a member of the Hsp60 family. Grasshopper testes, which synthesized negligible Hsp70 but abundant Hsp64 after heat shock, developed thermotolerance. Thus, heat shock response is modulated by developmental and environmental factors in different tissues of insects.
通过³⁵S-甲硫氨酸标记和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳荧光自显影技术，研究了自然种群的蝗虫和蟑螂以及实验室饲养的棉铃虫不同组织中热激蛋白（Hsp）在热诱导合成（37℃至45℃）时的模式。虽然在大多数情况下45℃是致死温度，但在37℃至42℃之间可观察到Hsp合成的最佳诱导。在这些温度下，正在进行的蛋白质合成受影响不大，除了成年棉铃虫暴露于42℃的组织。然而，昆虫组织中诱导产生的Hsp谱不同。根据70 kDa（Hsp70）和64 kDa（Hsp64）多肽合成的相对丰度，确定了三类热激反应：（1）诱导产生大量Hsp70但少量Hsp64（成年蝗虫的马氏管、雄性附腺和卵巢），（2）大量Hsp64但少量Hsp70（成年蝗虫的睾丸、成年蟑螂的睾丸和马氏管，以及棉铃虫幼虫的睾丸、马氏管和脂肪体），以及（3）Hsp70和Hsp64以大致相等的丰度诱导产生（成年蟑螂的卵巢、棉铃虫幼虫的唾液腺，以及成年棉铃虫的马氏管、雄性附腺、睾丸和卵巢）。从储藏室收集的蟑螂仅在热激后显示出可检测到的Hsp64和/或Hsp70合成，但从下水道收集的蟑螂在不同组织中未受热应激时就显示出可检测到的Hsp70和Hsp64合成。蛋白质免疫印迹法显示，这些昆虫中的64 kDa多肽是Hsp60家族的成员。热激后合成可忽略不计的Hsp70但大量合成Hsp64的蝗虫睾丸产生了耐热性。因此，热激反应在昆虫的不同组织中受到发育和环境因素的调节。
