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The Esg Gene Is Involved in Nicotine Sensitivity in Drosophila melanogaster.

Sanchez-Díaz I, Rosales-Bravo F, Reyes-Taboada JL, Covarrubias AA, Narvaez-Padilla V, Reynaud E - PLoS ONE (2015)

Bottom Line: Two fly lines, L4 and L70, whose HRT was significantly longer than control´s were identified.In this work, we demonstrate that esg loss of function induces nicotine sensitivity possibly by altering development of sensory organs and neurons in the medial section of the thoracoabdominal ganglion.The ectopic expression of the miR-310c also induces nicotine sensitivity by lowering Esg levels thus disrupting sensory organs and possibly to the modulation of other miR-310c targets.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad, 2001, Apartado Postal, 510-3, Cuernavaca 62210, México.

ABSTRACT
In humans, there is a strong correlation between sensitivity to substances of abuse and addiction risk. This differential tolerance to drugs has a strong genetic component. The identification of human genetic factors that alter drug tolerance has been a difficult task. For this reason and taking advantage of the fact that Drosophila responds similarly to humans to many drugs, and that genetically it has a high degree of homology (sharing at least 70% of genes known to be involved in human genetic diseases), we looked for genes in Drosophila that altered their nicotine sensitivity. We developed an instantaneous nicotine vaporization technique that exposed flies in a reproducible way. The amount of nicotine sufficient to "knock out" half of control flies for 30 minutes was determined and this parameter was defined as Half Recovery Time (HRT). Two fly lines, L4 and L70, whose HRT was significantly longer than control´s were identified. The L4 insertion is a loss of function allele of the transcriptional factor escargot (esg), whereas L70 insertion causes miss-expression of the microRNA cluster miR-310-311-312-313 (miR-310c). In this work, we demonstrate that esg loss of function induces nicotine sensitivity possibly by altering development of sensory organs and neurons in the medial section of the thoracoabdominal ganglion. The ectopic expression of the miR-310c also induces nicotine sensitivity by lowering Esg levels thus disrupting sensory organs and possibly to the modulation of other miR-310c targets.

No MeSH data available.


Related in: MedlinePlus

Expression pattern of the esg L4 enhancer trap.(A-C) L4>UAS-GFP third instar larval central nervous system (CNS) and adjacent imaginal discs A) Differential interference contrast (DIC) microscopy image. (B) Confocal maximal projection of an immunohistochemistry against GFP. Arrows show the medial section of the thoracoabdominal ganglion esg expressing neurons and arrowheads show mushroom bodies. (C) Overlay of DIC and confocal images. (D-F) L4>UAS-GFP third instar larval inverted maxillary region that includes labial imaginal discs. (D) DIC microscopy image. (E) Confocal maximal projection of GFP fluorescence. Arrows show the expression domain in the proximal labial discs. Arrowheads show mandibles. (F) Overlay of (D) and (E). (G-I) L4>UAS-Stinger late pupal proboscis. (G) DIC microscopy image. (H) Confocal maximal projection of stringer fluorescence. (I) Overlay of (H) and (I). White dash-lines show the border of the CNS and labial imaginal discs, respectively.
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pone.0133956.g007: Expression pattern of the esg L4 enhancer trap.(A-C) L4>UAS-GFP third instar larval central nervous system (CNS) and adjacent imaginal discs A) Differential interference contrast (DIC) microscopy image. (B) Confocal maximal projection of an immunohistochemistry against GFP. Arrows show the medial section of the thoracoabdominal ganglion esg expressing neurons and arrowheads show mushroom bodies. (C) Overlay of DIC and confocal images. (D-F) L4>UAS-GFP third instar larval inverted maxillary region that includes labial imaginal discs. (D) DIC microscopy image. (E) Confocal maximal projection of GFP fluorescence. Arrows show the expression domain in the proximal labial discs. Arrowheads show mandibles. (F) Overlay of (D) and (E). (G-I) L4>UAS-Stinger late pupal proboscis. (G) DIC microscopy image. (H) Confocal maximal projection of stringer fluorescence. (I) Overlay of (H) and (I). White dash-lines show the border of the CNS and labial imaginal discs, respectively.

Mentions: Trying to understand the cellular basis of these phenotypes, we characterized the L4 expression pattern by crossing it with UAS-GFP and found that it has the same expression pattern as the one reported for esg: embryonic ectoderm and histoblasts; larval leg and wing imaginal discs, brain, spiracles and tracheae; adult intestinal stem cells, malpighian tubules, testis and salivary glands [7,16–19]. Our data shows that esg is also expressed in the third instar larval mushroom bodies and the medial section of the thoracoabdominal ganglion, where motor neurons that innervate wings and legs are located. (Fig 7A–7C). Importantly, we found that esg is expressed in the proximal region of the third instar larvae labial imaginal discs (Fig 7D–7F) and in the labial palp of the late pupae (Fig 7G–7I) where the taste organs are developing. The lack of esg may be altering the normal differentiation of these organs causing hypersensitivity to nicotine.


The Esg Gene Is Involved in Nicotine Sensitivity in Drosophila melanogaster.

Sanchez-Díaz I, Rosales-Bravo F, Reyes-Taboada JL, Covarrubias AA, Narvaez-Padilla V, Reynaud E - PLoS ONE (2015)

Expression pattern of the esg L4 enhancer trap.(A-C) L4>UAS-GFP third instar larval central nervous system (CNS) and adjacent imaginal discs A) Differential interference contrast (DIC) microscopy image. (B) Confocal maximal projection of an immunohistochemistry against GFP. Arrows show the medial section of the thoracoabdominal ganglion esg expressing neurons and arrowheads show mushroom bodies. (C) Overlay of DIC and confocal images. (D-F) L4>UAS-GFP third instar larval inverted maxillary region that includes labial imaginal discs. (D) DIC microscopy image. (E) Confocal maximal projection of GFP fluorescence. Arrows show the expression domain in the proximal labial discs. Arrowheads show mandibles. (F) Overlay of (D) and (E). (G-I) L4>UAS-Stinger late pupal proboscis. (G) DIC microscopy image. (H) Confocal maximal projection of stringer fluorescence. (I) Overlay of (H) and (I). White dash-lines show the border of the CNS and labial imaginal discs, respectively.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4519288&req=5

pone.0133956.g007: Expression pattern of the esg L4 enhancer trap.(A-C) L4>UAS-GFP third instar larval central nervous system (CNS) and adjacent imaginal discs A) Differential interference contrast (DIC) microscopy image. (B) Confocal maximal projection of an immunohistochemistry against GFP. Arrows show the medial section of the thoracoabdominal ganglion esg expressing neurons and arrowheads show mushroom bodies. (C) Overlay of DIC and confocal images. (D-F) L4>UAS-GFP third instar larval inverted maxillary region that includes labial imaginal discs. (D) DIC microscopy image. (E) Confocal maximal projection of GFP fluorescence. Arrows show the expression domain in the proximal labial discs. Arrowheads show mandibles. (F) Overlay of (D) and (E). (G-I) L4>UAS-Stinger late pupal proboscis. (G) DIC microscopy image. (H) Confocal maximal projection of stringer fluorescence. (I) Overlay of (H) and (I). White dash-lines show the border of the CNS and labial imaginal discs, respectively.
Mentions: Trying to understand the cellular basis of these phenotypes, we characterized the L4 expression pattern by crossing it with UAS-GFP and found that it has the same expression pattern as the one reported for esg: embryonic ectoderm and histoblasts; larval leg and wing imaginal discs, brain, spiracles and tracheae; adult intestinal stem cells, malpighian tubules, testis and salivary glands [7,16–19]. Our data shows that esg is also expressed in the third instar larval mushroom bodies and the medial section of the thoracoabdominal ganglion, where motor neurons that innervate wings and legs are located. (Fig 7A–7C). Importantly, we found that esg is expressed in the proximal region of the third instar larvae labial imaginal discs (Fig 7D–7F) and in the labial palp of the late pupae (Fig 7G–7I) where the taste organs are developing. The lack of esg may be altering the normal differentiation of these organs causing hypersensitivity to nicotine.

Bottom Line: Two fly lines, L4 and L70, whose HRT was significantly longer than control´s were identified.In this work, we demonstrate that esg loss of function induces nicotine sensitivity possibly by altering development of sensory organs and neurons in the medial section of the thoracoabdominal ganglion.The ectopic expression of the miR-310c also induces nicotine sensitivity by lowering Esg levels thus disrupting sensory organs and possibly to the modulation of other miR-310c targets.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad, 2001, Apartado Postal, 510-3, Cuernavaca 62210, México.

ABSTRACT
In humans, there is a strong correlation between sensitivity to substances of abuse and addiction risk. This differential tolerance to drugs has a strong genetic component. The identification of human genetic factors that alter drug tolerance has been a difficult task. For this reason and taking advantage of the fact that Drosophila responds similarly to humans to many drugs, and that genetically it has a high degree of homology (sharing at least 70% of genes known to be involved in human genetic diseases), we looked for genes in Drosophila that altered their nicotine sensitivity. We developed an instantaneous nicotine vaporization technique that exposed flies in a reproducible way. The amount of nicotine sufficient to "knock out" half of control flies for 30 minutes was determined and this parameter was defined as Half Recovery Time (HRT). Two fly lines, L4 and L70, whose HRT was significantly longer than control´s were identified. The L4 insertion is a loss of function allele of the transcriptional factor escargot (esg), whereas L70 insertion causes miss-expression of the microRNA cluster miR-310-311-312-313 (miR-310c). In this work, we demonstrate that esg loss of function induces nicotine sensitivity possibly by altering development of sensory organs and neurons in the medial section of the thoracoabdominal ganglion. The ectopic expression of the miR-310c also induces nicotine sensitivity by lowering Esg levels thus disrupting sensory organs and possibly to the modulation of other miR-310c targets.

No MeSH data available.


Related in: MedlinePlus