Puffing patterns in polytene chromosomes of different tissues of Melanagromyza obtusa during development

Abstract

A completely new and improved system for the study of comparative puffing and banding patterns in different tissues of Meianagromyza obtusa during development is reported. A comparative study of puffing in polytene chromosomes of salivary and midgut epitheilal cells at the third instar larval and prepupal stages was made. Based on the behavior of these puffs, three categories of puffs were observed—common puffs, tissue-specific puffs, and stage-specific puffs. The functional significance of these puffs in relation to the cellular activity during development is discussed. In addition, the data on banding patterns between the homologous chromosomes in different tissues has further strengthened the concept of the constancy of banding patterns.