Takayama E, Motoyama M, Yoshida A
Dev Growth Differ. 1997 Aug;39(4):485-91. doi: 10.1046/j.1440-169x.1997.t01-3-00010.x.
It has been shown that microcautery on the prospective apical black region of the early pupal forewing of a butterfly, Pieris rapae, causes alteration of the scale color on the adult wing and a delay in histogenesis of the pupal wing. From these results, it has been assumed that the developmental delay of scale cells in the pupal wing alters their developmental fate and the hypothesis that different color fates of scales are determined by differences in the developmental timetables between scale cells is proposed. In this study, we attempted to find the developmental timetables of individual scales expressing specific color to test this hypothesis. It was found that the holes on the upper surface of a scale become larger as they develop and the hole sizes of scales in the white region are always larger than in the black region on the same wings either during pupal period or after eclosion. This suggests that the scale hole size is a good index that reflects developmental rate of the scale and a difference in the hole size between adult scales is attributed to a difference in the developmental timetables when their ancestral scale precursor cells were in the pupal period. A comparison of the hole sizes between adult scales in different color regions suggested that normal white scales were in a more advanced state than were the black ones but white scales induced by microcautery were in a less advanced state than black ones on the same wing. This supports our hypothesis.
研究表明，对菜粉蝶早期蛹前翅预期顶端黑色区域进行微烧灼，会导致成虫翅膀上鳞片颜色改变以及蛹翅组织发生延迟。基于这些结果，推测蛹翅中鳞片细胞的发育延迟改变了它们的发育命运，并提出了鳞片不同颜色命运由鳞片细胞发育时间表差异决定的假说。在本研究中，我们试图找出表达特定颜色的单个鳞片的发育时间表，以验证这一假说。结果发现，鳞片上表面的孔洞随着发育而变大，并且在蛹期或羽化后，同一翅膀上白色区域鳞片的孔洞大小总是大于黑色区域鳞片的孔洞大小。这表明鳞片孔洞大小是反映鳞片发育速率的良好指标，成虫鳞片之间孔洞大小的差异归因于其祖先鳞片前体细胞处于蛹期时发育时间表的差异。不同颜色区域成虫鳞片孔洞大小的比较表明，正常的白色鳞片比黑色鳞片处于更高级的状态，但同一翅膀上经微烧灼诱导产生的白色鳞片比黑色鳞片处于更不高级的状态。这支持了我们的假说。
