Drosophila glob1 expresses dynamically and is required for development and oxidative stress response

Biological significance of the globin protein family could be ascertained by their conservation through archaea to human. Globin(s) have been "classically" studied as oxygen binding protein(s), with recent implications in a host of other physiological functions. Drosophila melanogaster possesses three globin genes (glob1, glob2, glob3) located at different cytogenetic positions. We have performed a comprehensive investigation on the cellular expression profile and functional relevance of glob1 in Drosophila development. A profound level of maternally contributed glob1 gene products was found during early embryogenesis. Subsequently, commencement of zygotic transcription leads to its strong expression in somatic muscles, gut primordia, fat bodies, tracheal cells, etc. Similarly, dynamic expression of glob1 was evident in most of the larval tissues, interestingly with high expression in dividing cells. Reduced expression of glob1 leads to various impairments and lethality during embryogenesis and larval development. A substantial increase in level of cellular ROS was also evident due to reduced expression of glob1 which consequently leads to locomotor impairment and early aging in surviving adult flies. To best of our knowledge, this is the first report which demonstrates that in addition to oxygen management, globin gene(s) are also involved in regulating various aspects of development in Drosophila.