Sensory specificity and speciation: a potential neuronal pathway for host fruit odour discrimination in
            Rhagoletis pomonella

Behavioural changes in habitat or mate choice can trigger population divergence, leading to speciation. However, little is known about the neurological bases for such changes. Rhagoletis pomonella (Diptera: Tephritidae) is a model for ecological speciation via host plant shifts. Within the past 180 years, Rhagoletis flies infesting hawthorn ( Crataegus spp.) shifted to attack domesticated apple ( Malus pumila ). The two populations differ in their olfactory preferences for apple versus hawthorn fruit. Here, we looked for patterns of sensory organization that may have contributed to this shift by characterizing the morphology, specificity and distribution of olfactory sensory neurons (OSNs) on the antennae of Rhagoletis responding to host fruit and non-host volatiles. Of 28 OSN classes identified, two colocalized OSN pairs were found that specifically responded to the major behavioural attractant and antagonist volatiles for each fly population. A reversal in the response of these OSNs to fruit volatiles, either through a switch in receptor expression between these paired neurons or changes in neuronal projections in the brain, could therefore account for the behavioural difference between apple and hawthorn flies. The finding supports the hypothesis that relatively minor changes in olfactory sensory pathways may contribute to rapid host shifting and divergence in Rhagoletis .

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A field test for host fruit odour discrimination and avoidance behaviour for Rhagoletis pomonella flies in the western United States

Journal of Evolutionary Biology ◽

10.1111/j.1420-9101.2012.02489.x ◽

2012 ◽

Vol 25 (5) ◽

pp. 961-971 ◽

Cited By ~ 17

Author(s):

S. B. SIM ◽

M. MATTSSON ◽

JASMINE L. FEDER ◽

D. H. CHA ◽

W. L. YEE ◽

...

Keyword(s):

United States ◽

Field Test ◽

Avoidance Behaviour ◽

Western United States ◽

Rhagoletis Pomonella ◽

Host Fruit ◽

Odour Discrimination

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Phenotypic Characterization of the CD45+ and CD45− Plasma Cell Compartments in Monoclonal Gammopathies.

Blood ◽

10.1182/blood.v108.11.3505.3505 ◽

2006 ◽

Vol 108 (11) ◽

pp. 3505-3505

Author(s):

Teresa K. Kimlimger ◽

Michael M. Timm ◽

S. Vincent Rajkumar ◽

Jessica L. Haug ◽

Michael P. Kline ◽

...

Keyword(s):

Plasma Cells ◽

Cellular Adhesion ◽

Receptor Expression ◽

Phenotypic Characterization ◽

Vegf Receptor ◽

Myeloma Cells ◽

Monoclonal Gammopathies ◽

Normal Plasma ◽

Significant Difference ◽

Two Populations

Abstract Background: Multiple myeloma cells are heterogenous in terms of the expression of CD45 and previous studies have suggested important clinical and biological implications of the CD45 expression. It has been shown that expression of CD45 on myeloma cells has prognostic value and that the CD45 positive cells contain the proliferative fraction of the myeloma cells. We have also demonstrated that the CD45+ population has a higher apoptotic rate compared to CD45− cells. Given the hypothesis that CD45+ cells represent myeloma cells earlier in their development and are more proliferative and more dependent on the marrow microenvironment we studied differences between the two populations in patients with different stages of monoclonal gammopathies and in normal plasma cells. Methods: Fresh bone marrow aspirates were subjected to ACK lysis for removal of RBCs subjected to multicolor flow cytometry to study the expression of different surface antigens on the plasma cells. Plasma cells were identified based on their characteristic CD38/45 expression. The surface expression of CD19 (B cell marker), CD56 (NCAM), CD87, (involved in cellular adhesion, cell motility and angiogenesis), CD126 (IL-6 receptor alpha chain), sVEGF (surface VEGF; surrogate measure of VEGF receptor expression), and CD71 (proliferation marker) were studied and compared between the CD45 + and CD45− cells by gating separately on these populations. Results: Patients with active myeloma (76), smoldering myeloma (32), MGUS/amyloid (44), and normal patients (23) were studied. Not all markers were performed on all patients. Among the patient samples, the expression of CD19, CD87, CD71, CD126, and sVEGF were higher among the CD45+ cells compared to CD45− cells (Table: % of cells with expression). There was no significant difference between the two in terms of the expression of CD56. Among the normal plasma cells, the expression of CD19, CD87, CD126 and sVEGF was greater on the CD45+ cells compared to CD45− plasma cells and CD56 was not different. When the patient cells were compared to normal cells, the expression of CD19 was higher among the normal CD45+ plasma cells and CD56, CD87 and CD126 were less. The expression sVEGF was comparable Conclusion: In this study we demonstrate differences between CD45+ and CD45− plasma cells in patients with monoclonal gammopathies. These findings are important for understanding the disease biology and provide an insight into the functional differences seen between these two populations. The increased expression of CD19 in the CD45+ cells supports the notion that these cells are likely to be at an earlier developmental stage. The comparable CD56 expression is not in accordance with previous studies and needs to be examined in a larger group of patients. Increased expression of sVEGF and CD126 as well as the adhesion molecules is in accordance with increased responsiveness and dependence of the CD45+ cells to VEGF and IL-6 and the increased proliferative rates. These findings indirectly support the hypothesis that CD45 negative cells are less dependent on the marrow microenvironment and the cytokine milieu that it provides.

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Variation in host fruit volatiles attractive to apple maggot fly,Rhagoletis pomonella

Journal of Chemical Ecology ◽

10.1007/bf01020161 ◽

1987 ◽

Vol 13 (4) ◽

pp. 795-805 ◽

Cited By ~ 43

Author(s):

Sigrid A. Carle ◽

Anne L. Averill ◽

Geoffrey S. Rule ◽

W. Harvey Reissig ◽

Wendell L. Roelofs

Keyword(s):

Rhagoletis Pomonella ◽

Apple Maggot Fly ◽

Fruit Volatiles ◽

Host Fruit

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Genetic diversity of two Brazilian populations of the Pampas deer (Ozotoceros bezoarticus, Linnaeus 1758)

Brazilian Journal of Biology ◽

10.1590/s1519-69842007000500002 ◽

2007 ◽

Vol 67 (4 suppl) ◽

pp. 805-811 ◽

Cited By ~ 2

Author(s):

FP. Rodrigues ◽

JF. Garcia ◽

PRR. Ramos ◽

J. Bortolozzi ◽

JMB. Duarte

Keyword(s):

Genetic Variation ◽

Rapd Markers ◽

Random Amplified Polymorphic Dna ◽

Habitat Destruction ◽

Population Divergence ◽

Dispersal Patterns ◽

Mammal Species ◽

Management Guidelines ◽

Ozotoceros Bezoarticus ◽

Two Populations

The Pampas deer (Ozotoceros bezoarticus) is one of the most endangered Neotropical cervid with populations that have been drastically reduced to small and isolated ones, mainly because of its habitat destruction. Random amplified polymorphic DNA (RAPD) markers were used to analyze population divergence and genetic variation within and between two populations corresponding to distinct subspecies. The RAPD markers displayed substantial genetic variation with all animals possessing unique RAPD phenotypes over 105 polymorphic bands produced by 15 primers. An analysis of molecular variance (AMOVA) and a neighbor-joining cluster analysis were performed to assess levels of differentiation between populations. No differentiation was recorded and about 96.0% (P < 0.00001) of the total variance was attributable to variation within populations. This result is quite distinct from data obtained by the analysis of the mtDNA control region, and is discussed on the basis of genetic differences between the different markers and the male-biased dispersal patterns generally observed in the mammal species. The data presented herein are potentially useful for future taxonomic and genetic studies in this species, for the monitoring of the genetic variation observed within these populations, and for the development of management guidelines for its conservation.

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Identification of Host Fruit Volatiles from Domestic Apple (Malus domestica), Native Black Hawthorn (Crataegus douglasii) and Introduced Ornamental Hawthorn (C. monogyna) Attractive to Rhagoletis pomonella Flies from the Western United States

Journal of Chemical Ecology ◽

10.1007/s10886-012-0087-9 ◽

2012 ◽

Vol 38 (3) ◽

pp. 319-329 ◽

Cited By ~ 14

Author(s):

Dong H. Cha ◽

Wee L. Yee ◽

Robert B. Goughnour ◽

Sheina B. Sim ◽

Thomas H. Q. Powell ◽

...

Keyword(s):

United States ◽

Malus Domestica ◽

Western United States ◽

Rhagoletis Pomonella ◽

Fruit Volatiles ◽

Host Fruit

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MATING BEHAVIOR OF RHAGOLETIS POMONELLA (DIPTERA: TEPHRITIDAE): IV. COURTSHIP

The Canadian Entomologist ◽

10.4039/ent105873-6 ◽

1973 ◽

Vol 105 (6) ◽

pp. 873-891 ◽

Cited By ~ 35

Author(s):

Ronald J. Prokopy ◽

Guy L. Bush

Keyword(s):

Courtship Behavior ◽

Oviposition Behavior ◽

Sour Cherry ◽

Rhagoletis Pomonella ◽

Forward Movement ◽

Host Fruit ◽

Tactile Contact ◽

Large Populations ◽

Body Patterns ◽

Cherry Trees

AbstractThe results of systematically-conducted, mid- to late-season observations and experiments on large populations of apple maggot flies, Rhagoletis pomonella (Walsh), in apple and sour cherry trees revealed the following sequences in courtship behavior. When environmental conditions are favorable, sexually mature males and females fly to the host fruit, the site of assembly for mating and the site of oviposition. Either sex may initiate the flight which takes it to the particular fruit occupied by a member of the opposite sex. Such flights by males are often in response to the visual stimulus of a female (or male) moving about on a fruit, while such flights by females seem to be primarily in response to the fruit as a potential oviposition site. Once on the same fruit, a male and a female locate one another apparently solely through vision, particularly movement. They walk to within 1–3 cm of one another, but there is no tactile contact until such time as the male attempts copulation by jumping onto the back of the female from this distance.The position from which the copulatory jump is made is variable. Sometimes it is made from a face to face position, with one or both flies having waved its pictured wings at the other. Occasionally it is made from the side or from a flight from a nearby fruit directly onto a female’s abdomen. Most often however, it is made when a male is stimulated by the forward movement of a female, approaches her from the rear, and jumps onto her abdomen from the rear without the female having seen the male. Most copulation attempts, and especially most successful attempts, are initiated while the female is engaged in some phase of oviposition behavior. Males attempt copulation with other males just as often as with females, strongly suggesting that at least up until the time of tactile contact, males are unable to distinguish between the sexes. The fact that a number of male and female apple maggot flies was observed in copula with R. fausta flies in sour cherry trees suggests that neither sex may be able to discriminate too well between members of its own species and members of other species whose wing and body patterns are similar in appearance However males were usually, although not always, able to distinguish stable flies from apple maggot flies prior to tactile contact.We discuss the known and possible roles of various visual, chemical acoustical, and physical-tactile cues involved in the courtship behavior and suggest that the most important factor insuring reproductive isolation in apple maggot flies at the pre-copulatory stage may be the selection of the proper host plant for oviposition and hence for assembly for mating.

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