scholarly journals Gene duplicates cause hybrid lethality between sympatric species of Mimulus

2017 ◽  
Author(s):  
Matthew P. Zuellig ◽  
Andrea L. Sweigart
Keyword(s):  
Gene Flow ◽  
Critical Role ◽  
Sympatric Species ◽  
Mimulus Guttatus ◽  
Sympatric Populations ◽  
Genetic Incompatibility ◽  
Interspecific Gene Flow ◽  
Evolutionary Forces ◽  
Photosynthetic Gene ◽  
Functional Copy

AbstractHybrid incompatibilities play a critical role in the evolution and maintenance of species. We have discovered a simple genetic incompatibility that causes lethality in hybrids between two closely related species of yellow monkeyflower (Mimulus guttatus and M. nasutus). This hybrid incompatibility, which causes one sixteenth of F2 hybrid seedlings to lack chlorophyll and die shortly after germination, occurs between sympatric populations that are connected by ongoing interspecific gene flow. Using complimentary genetic mapping and gene expression analyses, we show that lethality occurs in hybrids that lack a functional copy of the critical photosynthetic gene pTAC14. In M. guttatus, this gene was duplicated, but the ancestral copy is no longer expressed. In M. nasutus, the duplication is missing altogether. As a result, hybrids die when they are homozygous for the nonfunctional M. guttatus copy and missing the duplicate from M. nasutus, apparently due to misregulated transcription of key photosynthetic genes. Our study indicates that neutral evolutionary processes may play an important role in the evolution of hybrid incompatibilities and opens the door to direct investigations of their contribution to reproductive isolation among naturally hybridizing species.Author SummaryHybrid incompatibilities play an important role in speciation, because they act to limit gene flow between species. Identifying the genes that underlie these barriers sheds light on the evolutionary forces and genetic mechanisms that give rise to new species. We identified a reproductive barrier that causes lethality in the F2 offspring of sympatric species of yellow monkeyflower (Mimulus guttatus and M. nasutus). We show that lethality occurs in hybrids that lack a functional copy of the critical photosynthetic gene pTAC14. This gene was duplicated in M. guttatus, but the ancestral copy subsequently lost function. In M. nasutus, no duplication occurred. As a consequence, F2 hybrids that are homozygous for non-functional M. guttatus copies at one locus and missing M. nasutus duplicates at the other locus completely lack functional pTAC14 and die. Our data indicate that non-functionalization of ancestral pTAC14 in M. guttatus occurred via neutral evolutionary change. These results suggest that neutral evolutionary forces may play an important role in speciation.

scholarly journals Genomic signals of admixture and reinforcement between two closely related species of European sepsid flies

2020 ◽  
Author(s):  
Athene Giesen ◽  
Wolf U. Blanckenhorn ◽  
Martin A. Schäfer ◽  
Kentaro K. Shimizu ◽  
Rie Shimizu-Inatsugi ◽  
...  
Keyword(s):  
Gene Flow ◽  
Dna Sequence ◽  
Species Boundaries ◽  
Adaptive Divergence ◽  
Sympatric Populations ◽  
Interspecific Gene Flow ◽  
Natural Systems ◽  
Sequence Identity ◽  
Interspecific Differences ◽  
Genome Wide

ABSTRACTInterspecific gene flow by hybridization may weaken species barriers and adaptive divergence, but can also initiate reinforcement of reproductive isolation trough natural and sexual selection. The extent of interspecific gene flow and its consequences for the initiation and maintenance of species barriers in natural systems remain poorly understood, however. To assess genome-wide patterns of gene flow between the two closely related European dung fly species Sepsis cynipsea and Sepsis neocynipsea (Diptera: Sepsidae), we tested for historical gene flow with the aid of ABBA-BABA test using whole-genome resequencing data from pooled DNA of male specimens originating from natural and laboratory populations. We contrasted genome-wide variation in DNA sequence differences between samples from sympatric populations of the two species in France and Switzerland with that of interspecific differences between pairs of samples involving allopatric populations from Estonia and Italy. In the French Cevennes, we detected a relative excess of DNA sequence identity, suggesting interspecific gene flow in sympatry. In contrast, at two sites in Switzerland, we observed a relative depletion of DNA sequence identity compatible with reinforcement of species boundaries in sympatry. Our results suggest that the species boundaries between S. cynipsea and S. neocynipsea in Europe depend on the eco-geographic context.

scholarly journals Genomic signals of admixture and reinforcement between two closely related species of European sepsid flies

2021 ◽  
Author(s):  
Athene Giesen ◽  
Wolf Blanckenhorn ◽  
Martin Schäfer ◽  
Kentaro K. Shimizu ◽  
Rie Shimizu-Inatsugi ◽  
...  
Keyword(s):  
Gene Flow ◽  
Dna Sequence ◽  
Species Boundaries ◽  
Adaptive Divergence ◽  
Sympatric Populations ◽  
Interspecific Gene Flow ◽  
Natural Systems ◽  
Sequence Identity ◽  
Interspecific Differences ◽  
Genome Wide

Interspecific gene flow by hybridization may weaken species barriers and adaptive divergence, but can also initiate reinforcement of reproductive isolation trough natural and sexual selection. The extent of interspecific gene flow and its consequences for the initiation and maintenance of species barriers in natural systems remain poorly understood, however. To assess genome-wide patterns of gene flow between the two closely related European dung fly species Sepsis cynipsea and Sepsis neocynipsea (Diptera: Sepsidae), we tested for historical gene flow with the aid of ABBA-BABA test using whole-genome resequencing data from pooled DNA of male specimens originating from natural and laboratory populations. We contrasted genome-wide variation in DNA sequence differences between samples from sympatric populations of the two species in France and Switzerland with that of interspecific differences between pairs of samples involving allopatric populations from Estonia and Italy. In the French Cevennes, we detected a relative excess of DNA sequence identity, suggesting interspecific gene flow in sympatry. In contrast, at two sites in Switzerland, we observed a relative depletion of DNA sequence identity compatible with reinforcement of species boundaries in sympatry. Our results suggest that the species boundaries between S. cynipsea and S. neocynipsea in Europe depend on the eco-geographic context.

scholarly journals Estimating the temporal and spatial extent of gene flow among sympatric lizard populations (genus Sceloporus) in the southern Mexican highlands

2014 ◽  
Author(s):  
Jared A Grummer ◽  
Martha L. Calderón ◽  
Adrián Nieto Montes-de Oca ◽  
Eric N Smith ◽  
Fausto Méndez-de la Cruz ◽  
...  
Keyword(s):  
Gene Flow ◽  
Ancestral Population ◽  
Secondary Contact ◽  
Sympatric Populations ◽  
Interspecific Gene Flow ◽  
Ancestral Gene ◽  
Mixed Support ◽  
Coalescent Simulations ◽  
Range Overlap ◽  
Analytical Approaches

Interspecific gene flow is pervasive throughout the tree of life. Although detecting gene flow between populations has been facilitated by new analytical approaches, determining the timing and geography of hybridization has remained difficult, particularly for historical gene flow. A geographically explicit phylogenetic approach is needed to determine the ancestral population overlap. In this study, we performed population genetic analyses, species delimitation, simulations, and a recently developed approach of species tree diffusion to infer the phylogeographic history, timing and geographic extent of gene flow in lizards of the Sceloporus spinosus group. The two species in this group, S. spinosus and S. horridus, are distributed in eastern and western portions of Mexico, respectively, but populations of these species are sympatric in the southern Mexican highlands. We generated data consisting of three mitochondrial genes and eight nuclear loci for 148 and 68 individuals, respectively. We delimited six lineages in this group, but found strong evidence of mito-nuclear discordance in sympatric populations of S. spinosus and S. horridus owing to mitochondrial introgression. We used coalescent simulations to differentiate ancestral gene flow from secondary contact, but found mixed support for these two models. Bayesian phylogeography indicated more than 60% range overlap between ancestral S. spinosus and S. horridus populations since the time of their divergence. Isolation-migration analyses, however, revealed near-zero levels of gene flow between these ancestral populations. Interpreting results from both simulations and empirical data indicate that despite a long history of sympatry among these two species, gene flow in this group has only recently occurred.

scholarly journals Maintaining their genetic distance; limited gene flow between widely hybridising species of Geum with contrasting mating systems

2017 ◽  
Author(s):  
Crispin Y. Jordan ◽  
Konrad Lohse ◽  
Frances Turner ◽  
Marian Thomson ◽  
Karim Gharbi ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Mating System ◽  
Draft Genome ◽  
Sympatric Populations ◽  
Species Classification ◽  
Interspecific Gene Flow ◽  
System Transition ◽  
Tentative Evidence ◽  
Limited Gene Flow

AbstractMating system transition from outcrossing to selfing frequently gives rise to sister lineages with contrasting outcrossing rates. The evolutionary fate of such lineages depends on the extent to which they exchange genes. We measured gene flow between outcrossing Geum rivale and selfing G. urbanum, two sister species derived by mating system transition, which frequently hybridise. A draft genome was generated for G. urbanum and used to develop dd-RAD data scorable in both species. Coalescent analysis of RAD data from allopatric populations indicated that the two species diverged 2-3 Mya, and that long term gene flow between them has been very low (M=0.04). G. rivale showed greater genetic diversity in sympatry than allopatry, but genetic divergence between species was no lower in sympatry than allopatry, providing little evidence for recent introgression. Clustering of genotypes revealed that, apart from four early generation hybrids, individuals in sympatric populations fell into two genetically distinct groups with <1% admixture that corresponded exactly to their morphological species classification. Although our data suggest limited gene flow, we observed joint segregation of two putatively introgressed SNPs in G. urbanum populations that was associated with significant morphological variation; this provides tentative evidence for rare introduction of novel genetic diversity by interspecific gene flow. Our results indicate that despite frequent hybridisation, genetic exchange between G. rivale and G. urbanum has been very limited throughout their evolutionary history.

Interspecific gene flow and an intermediate molecular profile of Dyckia julianae (Bromeliaceae), an endemic species from southern Brazil

2019 ◽  
Vol 192 (4) ◽  
pp. 675-690 ◽  
Author(s):  
Luiza D Hirsch ◽  
Camila M Zanella ◽  
Camila Aguiar-Melo ◽  
Laís M S Costa ◽  
Fernanda Bered
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
The Other ◽  
Hybrid Origin ◽  
Molecular Profile ◽  
Southern Brazil ◽  
Sympatric Populations ◽  
Interspecific Gene Flow ◽  
Viable Seeds ◽  
Origin Hypothesis

Abstract When related species are distributed in sympatric populations, hybridization may occur. Likewise, one or more of these species may have arisen through historical hybridization between taxa. Here, we aim to elucidate the occurrence of hybridization among three Dyckia spp. (Bromeliaceae) from southern Brazil. We used seven nuclear and six plastid microsatellite loci to assess patterns of genetic diversity, population structure and hybridization in the three species. Furthermore, we performed manual crosses between species to test compatibility and fertility. The results showed that Dyckia julianae has an intermediate molecular profile, low gene flow occurs between Dyckia hebdingii and Dyckia choristaminea and higher gene flow occurs between D. julianae and the other two species. Plastid microsatellites identified 12 haplotypes that are shared among the species. The manual crosses between D. julianae and the other two species produced viable seeds, but no crosses between D. hebdingii and D. choristaminea generated fruits. Our data suggest that the reproductive barrier between D. julianae and the other two species is permeable. Further investigation into the hybrid origin hypothesis of D. julianae should be undertaken, as well as the mechanisms involved in reproductive isolation between D. hebdingii and D. choristaminea.

scholarly journals Premating barriers in young sympatric snail species

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Arina L. Maltseva ◽  
Marina A. Varfolomeeva ◽  
Arseniy A. Lobov ◽  
Polina O. Tikanova ◽  
Egor A. Repkin ◽  
...  
Keyword(s):  
Gene Flow ◽  
Snail Species ◽  
Sympatric Populations ◽  
Gastropod Species ◽  
Shell Size ◽  
Closely Related Species ◽  
Partial Canonical Correspondence Analysis ◽  
In The Wild ◽  
Isolation Index

AbstractSympatric coexistence of recently diverged species raises the question of barriers restricting the gene flow between them. Reproductive isolation may be implemented at several levels, and the weakening of some, e.g. premating, barriers may require the strengthening of the others, e.g. postcopulatory ones. We analysed mating patterns and shell size of mates in recently diverged closely related species of the subgenus Littorina Neritrema (Littorinidae, Caenogastropoda) in order to assess the role of premating reproductive barriers between them. We compared mating frequencies observed in the wild with those expected based on relative densities using partial canonical correspondence analysis. We introduced the fidelity index (FI) to estimate the relative accuracy of mating with conspecific females and precopulatory isolation index (IPC) to characterize the strength of premating barriers. The species under study, with the exception of L. arcana, clearly demonstrated preferential mating with conspecifics. According to FI and IPC, L. fabalis and L. compressa appeared reliably isolated from their closest relatives within Neritrema. Individuals of these two species tend to be smaller than those of the others, highlighting the importance of shell size changes in gastropod species divergence. L. arcana males were often found in pairs with L. saxatilis females, and no interspecific size differences were revealed in this sibling species pair. We discuss the lack of discriminative mate choice in the sympatric populations of L. arcana and L. saxatilis, and possible additional mechanisms restricting gene flow between them.

scholarly journals Molecular Signatures of Reticulate Evolution within the Complex of European Pine Taxa

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 489
Author(s):  
Bartosz Łabiszak ◽  
Witold Wachowiak
Keyword(s):  
Gene Flow ◽  
Reticulate Evolution ◽  
Modeling Framework ◽  
Closely Related Species ◽  
Interspecific Gene Flow ◽  
Nucleotide Sequence Variation ◽  
History Of ◽  
Best Fitting ◽  
Species Integrity

Speciation mechanisms, including the role of interspecific gene flow and introgression in the emergence of new species, are the major focus of evolutionary studies. Inference of taxonomic relationship between closely related species may be challenged by past hybridization events, but at the same time, it may provide new knowledge about mechanisms responsible for the maintenance of species integrity despite interspecific gene flow. Here, using nucleotide sequence variation and utilizing a coalescent modeling framework, we tested the role of hybridization and introgression in the evolutionary history of closely related pine taxa from the Pinus mugo complex and P. sylvestris. We compared the patterns of polymorphism and divergence between taxa and found a great overlap of neutral variation within the P. mugo complex. Our phylogeny reconstruction indicated multiple instances of reticulation events in the past, suggesting an important role of interspecific gene flow in the species divergence. The best-fitting model revealed P. mugo and P. uncinata as sister species with basal P. uliginosa and asymmetric migration between all investigated species after their divergence. The magnitude of interspecies gene flow differed greatly, and it was consistently stronger from representatives of P. mugo complex to P. sylvestris than in the opposite direction. The results indicate the prominent role of reticulation evolution in those forest trees and provide a genetic framework to study species integrity maintained by selection and local adaptation.

scholarly journals Interspecific Gene Flow Shaped the Evolution of the Genus Canis

2019 ◽  
Vol 29 (23) ◽  
pp. 4152 ◽  
Author(s):  
Shyam Gopalakrishnan ◽  
Mikkel-Holger S. Sinding ◽  
Jazmín Ramos-Madrigal ◽  
Jonas Niemann ◽  
Jose A. Samaniego Castruita ◽  
...  
Keyword(s):  
Gene Flow ◽  
Interspecific Gene Flow

Pleistocene survival, regional genetic structure and interspecific gene flow among three northern peat-mosses: Sphagnum inexspectatum , S. orientale and S. miyabeanum

2014 ◽  
Vol 42 (2) ◽  
pp. 364-376 ◽  
Author(s):  
A. Jonathan Shaw ◽  
Blanka Shaw ◽  
Hans K. Stenøien ◽  
G. Karen Golinski ◽  
Kristian Hassel ◽  
...  
Keyword(s):  
Gene Flow ◽  
Genetic Structure ◽  
Interspecific Gene Flow

scholarly journals Gene Flow in Phaseolus Beans and Its Role as a Plausible Driver of Ecological Fitness and Expansion of Cultigens

2021 ◽  
Vol 9 ◽  
Author(s):  
María Isabel Chacón-Sánchez ◽  
Jaime Martínez-Castillo ◽  
Jorge Duitama ◽  
Daniel G. Debouck
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Time Perspective ◽  
Lima Bean ◽  
Breeding Systems ◽  
Large Contribution ◽  
Interspecific Gene Flow ◽  
Ecological Fitness ◽  
Technological Advances ◽  
Evolutionary Force

The genus Phaseolus, native to the Americas, is composed of more than eighty wild species, five of which were domesticated in pre-Columbian times. Since the beginning of domestication events in this genus, ample opportunities for gene flow with wild relatives have existed. The present work reviews the extent of gene flow in the genus Phaseolus in primary and secondary areas of domestication with the aim of illustrating how this evolutionary force may have conditioned ecological fitness and the widespread adoption of cultigens. We focus on the biological bases of gene flow in the genus Phaseolus from a spatial and time perspective, the dynamics of wild-weedy-crop complexes in the common bean and the Lima bean, the two most important domesticated species of the genus, and the usefulness of genomic tools to detect inter and intraspecific introgression events. In this review we discuss the reproductive strategies of several Phaseolus species, the factors that may favor outcrossing rates and evidence suggesting that interspecific gene flow may increase ecological fitness of wild populations. We also show that wild-weedy-crop complexes generate genetic diversity over which farmers are able to select and expand their cultigens outside primary areas of domestication. Ultimately, we argue that more studies are needed on the reproductive biology of the genus Phaseolus since for most species breeding systems are largely unknown. We also argue that there is an urgent need to preserve wild-weedy-crop complexes and characterize the genetic diversity generated by them, in particular the genome-wide effects of introgressions and their value for breeding programs. Recent technological advances in genomics, coupled with agronomic characterizations, may make a large contribution.

Sign in / Sign up

Export Citation Format

Share Document