Article
Environmental Sciences
Yunyun Lv, Yanping Li, Yi Liu, Zhengyong Wen, Yexin Yang, Chuanjie Qin, Qiong Shi, Xidong Mu
Summary: This study generated a high-quality genome assembly and gene annotation of Midas cichlid, providing a valuable genetic resource for biological studies on this species. Through comparisons between dark and gold individuals, differential expressional genes and key functional modules were identified, enhancing our understanding of the transcriptional regulatory mechanisms underlying coloration changes. This research is of great importance not only for Midas cichlid, but also for other fish species in freshwater to marine ecosystems.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Sabine Urban, Alexander Nater, Axel Meyer, Claudius F. Kratochwil
Summary: In this study, researchers found that in Lake Malawi, the melanic horizontal stripes in cichlid fish are associated with recent de novo mutations near the agrp2 gene, whereas in Lake Victoria, the stripes are linked to two intronic regions. The haplotypes associated with these traits predate the Lake Victoria radiation and indicate a standing genetic variation driving phenotypic divergence. Both new and ancient allelic variation at the same locus fueled rapid and convergent phenotypic evolution.
MOLECULAR BIOLOGY AND EVOLUTION
(2021)
Review
Evolutionary Biology
M. Emilia Santos, Joao F. Lopes, Claudius F. Kratochwil
Summary: Cichlid fishes are a diverse family of teleost fishes found in lakes and rivers across India, Africa, and South and Central America. Most research has focused on East African cichlids in the Rift Lakes, which are biodiversity hotspots. This review provides an overview of the study system, research questions, and methodologies, covering various disciplines such as ecology, evolution, genetics, and behavior. The integration of traits and research disciplines, along with advances in genetic manipulations, has made cichlid fishes a fascinating research system.
Review
Ecology
Tanja C. Zerulla, Philip K. Stoddard
Summary: Melanin-based color patterns provide a novel model for studying molecular and evolutionary mechanisms, with spotted morphs in G. holbrooki and X. variatus exhibiting higher stress resistance, basal cortisol levels, and selective advantage. Findings conflict on whether different morphs differ in sexual behavior and sexual selection, and spotted morphs show strong selective advantage in predation events.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2021)
Editorial Material
Cell Biology
Francisco Javier Gil Etayo, Jairo Eduardo Nino Ramirez, Pilar Terradillos Sanchez, Ramon Garcia Sanz, Amalia Tejeda Velarde
Summary: A synonymous substitution in exon 2 and intronic insertion lead to the emergence of the novel HLA-DQA1*01:04:07 allele.
Article
Biotechnology & Applied Microbiology
Nicolas S. M. Robert, Fatih Sarigol, Bob Zimmermann, Axel Meyer, Christian R. Voolstra, Oleg Simakov
Summary: This study analyzed 49 animal genomes and discovered the largest gains of synteny in the last common ancestor of bilaterians and cnidarians. Depending on their node of emergence, the novel syntenic blocks exhibit distinct functional compositions and gene density properties. These findings provide insights into the regulatory properties of microsyntenic blocks in animal genomes.
Article
Evolutionary Biology
Mark D. Scherz, Paul Masonick, Axel Meyer, C. Darrin Hulsey
Summary: Whole genome sequences provide important evidence for our understanding of phylogenetic relationships, but they may not be able to resolve the evolutionary history of rapidly radiating lineages. Integrating results from different methods and using phylogenomic approaches can help overcome these challenges.
SYSTEMATIC BIOLOGY
(2022)
Article
Ecology
Sabine Urban, Jan Gerwin, C. Darrin Hulsey, Axel Meyer, Claudius F. Kratochwil
Summary: Color patterns are linked to the behavioral and morphological characteristics of animals, and play an important role in antipredatory strategies. This study finds a strong correlation between stripe patterns and body elongation in cichlid fish, indicating that the effectiveness of the stripes as an antipredatory strategy depends on body shape. However, genetic analyses show that stripes and body elongation segregate independently, suggesting that their correlation is maintained by correlational selection rather than genetic linkage. Furthermore, mate preference tests indicate that females do not differentiate between striped and nonstriped males, suggesting that stripes might be less important for species recognition and mate choice.
ECOLOGY AND EVOLUTION
(2022)
Article
Biochemistry & Molecular Biology
Camila L. Nacif, Claudius F. Kratochwil, Andreas F. Kautt, Alexander Nater, Gonzalo Machado-Schiaffino, Axel Meyer, Frederico Henning
Summary: The evolution and differentiation of sex chromosomes is a significant event in genome evolution, and the repeated evolution and variability of sex-determination mechanisms in fishes make them a suitable model for studying general patterns in evolution. This study used forward-genetics, long-read sequencing, and optical mapping to determine that sex in Midas cichlids is determined by an XY system and identified and assembled the sex-determining region. The study also found that the male-specific region on chromosome 4 contains transposable elements and a Y-specific duplicate of the anti-Mullerian receptor 2 gene, which has evolved as a master sex-determining gene. The duplication of anti-Mullerian genes is a common mechanism for establishing new sex determiners, highlighting the importance of molecular parallelism in the evolution of sex determination.
Article
Ecology
Claudius F. Kratochwil, Andreas F. Kautt, Sina J. Rometsch, Axel Meyer
Summary: High-throughput DNA sequencing technologies have made it easier to sequence entire genomes. Whole-genome resequencing can help identify and describe species that are difficult to discern, but it can be costly and time-consuming. Species-specific markers can be designed based on whole-genome resequencing data, enabling rapid and reliable species identification at a lower cost.
ECOLOGY AND EVOLUTION
(2022)
Article
Evolutionary Biology
Claudius F. Kratochwil, Yipeng Liang, Jan Gerwin, Paolo Franchini, Axel Meyer
Summary: This study investigates the differences between striped and nonstriped cichlid fishes in different lineages of Lake Victoria and Lake Malawi. The gene agrp2 is found to be associated with stripe pattern divergence. The study also examines the development of stripe patterns and vertical bar patterns, and suggests that the stripe phenotype may be caused by a combination of subtle transcriptomic differences or cellular changes.
EVOLUTION & DEVELOPMENT
(2022)
Review
Evolutionary Biology
M. Emilia Santos, Joao F. Lopes, Claudius F. Kratochwil
Summary: Cichlid fishes are a diverse family of teleost fishes found in lakes and rivers across India, Africa, and South and Central America. Most research has focused on East African cichlids in the Rift Lakes, which are biodiversity hotspots. This review provides an overview of the study system, research questions, and methodologies, covering various disciplines such as ecology, evolution, genetics, and behavior. The integration of traits and research disciplines, along with advances in genetic manipulations, has made cichlid fishes a fascinating research system.
Article
Evolutionary Biology
Jukka Jernvall, Nicolas Di-Poi, Marja L. L. Mikkola, Claudius F. F. Kratochwil
Summary: The development of an individual must have the ability to withstand the negative effects of both internal and external disruptions. This ability is called robustness and it is important for differentiating between normal variation and disease. Some systems and organs are more adaptable in correcting internal perturbations, such as mutations, while others are more resilient against external disturbances, like changes in temperature. In order to understand robustness, a comparative framework is necessary.
EVOLUTION & DEVELOPMENT
(2023)
Article
Evolutionary Biology
Paul Masonick, Axel Meyer, Christopher Darrin Hulsey
Summary: The genomic loci underlying variation in vertebrate structures like lips are surprisingly predictable. Both adaptive and maladaptive variation in traits such as jaws and teeth can be structured by the same genes in evolutionarily disparate organisms like teleost fishes and mammals. The recurrence of hypertrophied lips in cichlid fish lineages suggests the presence of shared genetic bases and potential insights into the genetic factors influencing human craniofacial anomalies.
GENOME BIOLOGY AND EVOLUTION
(2023)
Article
Biochemistry & Molecular Biology
Ralf F. Schneider, Helen M. Gunter, Inken Salewski, Joost M. Woltering, Axel Meyer
Summary: Evolutionary novelties can promote ecological specialization and adaptive radiations. Belonoid fishes, such as flying fishes, halfbeaks, and needlefishes, have highly diversified elongated jaw phenotypes. In this study, the development of elongated jaws in a halfbeak and a needlefish was investigated, revealing that these jaws consist of distinct base and extension portions. The growth dynamics of both bases and extensions were described, and the molecular mechanisms underlying the extension outgrowth were deduced.