TY - JOUR

T1 - Photosensitive Alternative Splicing of the Circadian Clock Gene timeless Is Population Specific in a Cold-Adapted Fly, Drosophila montana

AU - Tapanainen, Riikka

AU - Parker, Darren J

AU - Kankare, Maaria

N1 - Copyright © 2018 Tapanainen et al.

PY - 2018/4/1

Y1 - 2018/4/1

N2 - To function properly, organisms must adjust their physiology, behavior and metabolism in response to a suite of varying environmental conditions. One of the central regulators of these changes is organisms' internal circadian clock, and recent evidence has suggested that the clock genes are also important in the regulation of seasonal adjustments. In particular, thermosensitive splicing of the core clock gene timeless in a cosmopolitan fly, Drosophila melanogaster, has implicated this gene to be involved in thermal adaptation. To further investigate this link we examined the splicing of timeless in a northern malt fly species, Drosophila montana, which can withstand much colder climatic conditions than its southern relative. We studied northern and southern populations from two different continents (North America and Europe) to find out whether and how the splicing of this gene varies in response to different temperatures and day lengths. Interestingly, we found that the expression of timeless splice variants was sensitive to differences in light conditions, and while the flies of all study populations showed a change in the usage of splice variants in constant light compared to LD 22:2, the direction of the shift varied between populations. Overall, our findings suggest that the splicing of timeless in northern Drosophila montana flies is photosensitive, rather than thermosensitive and highlights the value of studying multiple species and populations in order to gain perspective on the generality of gene function changes in different kinds of environmental conditions.

AB - To function properly, organisms must adjust their physiology, behavior and metabolism in response to a suite of varying environmental conditions. One of the central regulators of these changes is organisms' internal circadian clock, and recent evidence has suggested that the clock genes are also important in the regulation of seasonal adjustments. In particular, thermosensitive splicing of the core clock gene timeless in a cosmopolitan fly, Drosophila melanogaster, has implicated this gene to be involved in thermal adaptation. To further investigate this link we examined the splicing of timeless in a northern malt fly species, Drosophila montana, which can withstand much colder climatic conditions than its southern relative. We studied northern and southern populations from two different continents (North America and Europe) to find out whether and how the splicing of this gene varies in response to different temperatures and day lengths. Interestingly, we found that the expression of timeless splice variants was sensitive to differences in light conditions, and while the flies of all study populations showed a change in the usage of splice variants in constant light compared to LD 22:2, the direction of the shift varied between populations. Overall, our findings suggest that the splicing of timeless in northern Drosophila montana flies is photosensitive, rather than thermosensitive and highlights the value of studying multiple species and populations in order to gain perspective on the generality of gene function changes in different kinds of environmental conditions.

KW - 3' Untranslated Regions/genetics

KW - Adaptation, Physiological/genetics

KW - Alternative Splicing/genetics

KW - Analysis of Variance

KW - Animals

KW - Base Sequence

KW - Circadian Clocks/genetics

KW - Cold Temperature

KW - Drosophila/genetics

KW - Drosophila Proteins/genetics

KW - Female

KW - Genes, Insect

KW - Geography

KW - Introns/genetics

KW - Light

KW - Mutation/genetics

U2 - 10.1534/g3.118.200050

DO - 10.1534/g3.118.200050

M3 - Article

C2 - 29472309

VL - 8

SP - 1291

EP - 1297

JO - G3: Genes, Genomes, Genetics

JF - G3: Genes, Genomes, Genetics

SN - 2160-1836

IS - 4

ER -