Open AccessSensitivity to expression levels underlies differential dominance of a putative null allele of the Drosophila tßh gene in behavioral phenotypes
Author(s) -
Christine Damrau,
Julien Colomb,
Björn Brembs
Publication year - 2021
Publication title -
plos biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.127
H-Index - 271
eISSN - 1545-7885
pISSN - 1544-9173
DOI - 10.1371/journal.pbio.3001228
Subject(s) - biology , drosophila melanogaster , phenotype , allele , genetics , null allele , mutant , gene , tyramine , transgene , gene expression , dominance (genetics) , octopamine (neurotransmitter) , microbiology and biotechnology , receptor , endocrinology , serotonin
The biogenic amine octopamine (OA) and its precursor tyramine (TA) are involved in controlling a plethora of different physiological and behavioral processes. The tyramine- β- hydroxylase ( t β h ) gene encodes the enzyme catalyzing the last synthesis step from TA to OA. Here, we report differential dominance (from recessive to overdominant) of the putative null t β h nM18 allele in 2 behavioral measures in Buridan’s paradigm (walking speed and stripe deviation) and in proboscis extension (sugar sensitivity) in the fruit fly Drosophila melanogaster . The behavioral analysis of transgenic t β h expression experiments in mutant and wild-type flies as well as of OA and TA receptor mutants revealed a complex interaction of both aminergic systems. Our analysis suggests that the different neuronal networks responsible for the 3 phenotypes show differential sensitivity to t β h gene expression levels. The evidence suggests that this sensitivity is brought about by a TA/OA opponent system modulating the involved neuronal circuits. This conclusion has important implications for standard transgenic techniques commonly used in functional genetics.