Laurence Zwiebel - Academia.edu (original) (raw)

Uploads

Papers by Laurence Zwiebel

Insects

Over the past decade, spurred in part by the sequencing of the first ant genomes, there have been... more Over the past decade, spurred in part by the sequencing of the first ant genomes, there have been major advances in the field of olfactory myrmecology. With the discovery of a significant expansion of the odorant receptor gene family, considerable efforts have been directed toward understanding the olfactory basis of complex social behaviors in ant colonies. Here, we review recent pivotal studies that have begun to reveal insights into the development of the olfactory system as well as how olfactory stimuli are peripherally and centrally encoded. Despite significant biological and technical impediments, substantial progress has been achieved in the application of gene editing and other molecular techniques that notably distinguish the complex olfactory system of ants from other well-studied insect model systems, such as the fruit fly. In doing so, we hope to draw attention not only to these studies but also to critical knowledge gaps that will serve as a compass for future research ...

Alignment and phylogenetic tree of OR61. (PDF 1577 kb)

Comparison with previously published A. albopictus OBP. (XLSX 14 kb)

Alignment of Atypical OBPs. (PDF 8211 kb)

Alignment of PlusC OBPs. (PDF 4328 kb)

Dataset S3. Transcriptome: differential expression analysis. (XLSX 14649 kb)

Alignment of Classic OBPs.(PDF 7646 kb)

Dataset S2. Transcriptome: comparisons with databases. (XLSX 15138 kb)

Correlation of biological replicates. (PDF 951 kb)

Features of primers used in this study.(PDF 44 kb)

IR7 genetic cluster. (PDF 250 kb)

IR111.2 gene family in Ae. albopictus. (PDF 144 kb)

Alignment files. MEGA files of protein alignments and tree. (ZIP 93 kb)

Alignment and phylogenetic tree of IR41p1. (PDF 1841 kb)

Chemosensory proteins in the different samples and average TPM. (PDF 41 kb)

Anopheline mosquitoes are the sole vectors for the Plasmodium pathogens responsible for malaria, ... more Anopheline mosquitoes are the sole vectors for the Plasmodium pathogens responsible for malaria, which is among the oldest and most devastating of human diseases. The continuing global impact of malaria reflects the evolutionary success of a complex vector-pathogen relationship that accordingly has been the long-term focus of both debate and study. An open question in the biology of malaria transmission is the impact of naturally occurring low-level Plasmodium infections of the vector on the mosquito’s health and longevity as well as critical behaviors such as host-preference/seeking. To begin to answer this, we have completed a comparative RNAseq-based transcriptome profile study examining the effect of biologically salient, salivary gland transmission-stage Plasmodium infection on the molecular physiology of Anopheles gambiae s.s. head, sensory appendage, and salivary glands. When compared with their uninfected counterparts, Plasmodium infected mosquitoes exhibit increased transcr...

Anopheline mosquitoes are the sole vectors of malaria and rely on olfactory cues for host seeking... more Anopheline mosquitoes are the sole vectors of malaria and rely on olfactory cues for host seeking in which ammonia derived from human sweat plays an essential role. To investigate the function of the Anopheles coluzzii ammonium transporter (AcAmt) in the mosquito olfactory system, we generated an AcAmt null mutant line using CRISPR/Cas9. AcAmt-/- mutants displayed a series of novel phenotypes compared with wild-type mosquitoes including significantly lower insemination rates during mating and increased mortality during eclosion. Furthermore, AcAmt-/- males showed significantly lower sugar consumption while AcAmt-/- females and pupae displayed significantly higher ammonia levels than their wild-type counterparts. Surprisingly, in contrast to previous studies in Drosophila that revealed that the mutation of the ammonium transporter (DmAmt) induces a dramatic reduction of ammonia responses in antennal coeloconic sensilla, no significant differences were observed across a range of perip...

BackgroundIn eusocial ants, aggressive behaviors require a sophisticated ability to detect and di... more BackgroundIn eusocial ants, aggressive behaviors require a sophisticated ability to detect and discriminate between chemical signatures such as cuticular hydrocarbons that distinguish nestmate friends from non-nestmate foes. It has been suggested that a mismatch between a chemical signature (label) and the internal, neuronal representation of the colony odor (template) leads to the recognition of and subsequent aggression between non-nestmates. While several studies have demonstrated that ant chemosensory systems, most notably olfaction, are largely responsible for the decoding of these chemical signatures, a definitive demonstration that odorant receptors are responsible for the detection and processing of the pheromonal signals that regulate nestmate recognition has thus far been lacking. To address this, we have developed an aggression-based bioassay incorporating a suite of highly selective odorant receptor modulators to characterize the role of olfaction in nestmate recognition...

Genome biology and evolution, Jan 12, 2015

Eusocial insects, mostly Hymenoptera, have evolved unique colonial lifestyles that rely on the pe... more Eusocial insects, mostly Hymenoptera, have evolved unique colonial lifestyles that rely on the perception of social context mainly through pheromones, and chemoreceptors are hypothesized to have played important adaptive roles in the evolution of sociality. However, because chemoreceptor repertoires have been characterized in few social insects and their solitary relatives, a comprehensive examination of this hypothesis has not been possible. Here, we annotate ∼3,000 odorant and gustatory receptors in recently sequenced Hymenoptera genomes and systematically compare >4,000 chemoreceptors from 13 hymenopterans, representing one solitary lineage (wasps) and three independently evolved eusocial lineages (ants and two bees). We observe a strong general tendency for chemoreceptors to expand in Hymenoptera, whereas the specifics of gene gains/losses are highly diverse between lineages. We also find more frequent positive selection on chemoreceptors in a facultative eusocial bee and in ...

A comparative transcriptomic study of mosquito olfactory tissues recently published in BMC Genomi... more A comparative transcriptomic study of mosquito olfactory tissues recently published in BMC Genomics (Hodges et al., 2014) reported several novel findings that have broad implications for the field of insect olfaction. In this brief commentary, we outline why the conclusions of Hodges et al. are problematic under the current models of insect olfaction and then contrast their findings with those of other RNAseq based studies of mosquito olfactory tissues. We also generated a new RNAseq data set from the maxillary palp of Anopheles gambiae in an effort to replicate the novel results of Hodges et al. but were unable to reproduce their results. Instead, our new RNAseq data support the more straightforward explanation that the novel findings of Hodges et al. were a consequence of contamination by antennal RNA. In summary, we find strong evidence to suggest that the conclusions of Hodges et al were spurious, and that at least some of their RNAseq data sets were irrevocably compromised by c...