Article
Genetics & Heredity
Betty M. N. Furulund, Bard O. Karlsen, Igor Babiak, Peik Haugen, Steinar D. Johansen
Summary: Group I introns in myxomycetes, a distinct protist phylum, exhibit dynamic structures and complex inheritance patterns. The consensus secondary structure reveals a conserved core and RNA sequence complexity in the peripheral regions. These introns possess various structural organizations, including twintron organization and direct repeat arrays. Phylogenetic analyses indicate both vertical and horizontal transfers. The evolutionary history involves the insertion of mobile-type introns, degradation of homing endonuclease genes, and ultimately complete loss of the introns.
Article
Genetics & Heredity
Kjersti Lian, Betty M. N. Furulund, Anders A. Tveita, Peik Haugen, Steinar D. Johansen
Summary: The study analyzed nuclear L2066 group I introns from myxomycetes and ascomycetes, revealing the presence of mobile-type introns with homing endonuclease genes. In vitro and in vivo experiments demonstrated the mechanism of double-strand break at the DNA insertion site by these introns.
Article
Biochemistry & Molecular Biology
Dario Monachello, Marc Lauraine, Sandra Gillot, Francois Michel, Maria Costa
Summary: Mobile group II introns are retrotransposable elements that insert themselves into DNA target sites with the help of base-pairing interactions and the reverse transcriptase enzyme. A new base-pairing interaction named EBS2a-IBS2a has been identified, which is crucial for intron mobility by driving unwinding of the DNA duplex and is stabilized by the reverse transcriptase in a non-sequence-specific manner. This discovery has important implications for the biotechnological applications of group II introns in bacterial gene targeting.
NUCLEIC ACIDS RESEARCH
(2021)
Article
Oceanography
Alex Cranston, Sergi Taboada, Vasiliki Koutsouveli, Astrid Schuster, Ana Riesgo
Summary: Self-splicing mitochondrial introns are rare in animals, with this study describing one found in only certain populations of the sponge Phakellia robusta in the North-east Atlantic. The intron was only present in shallow populations spanning from Ireland to Norway, possibly linked to past hybridization events. Further analysis is needed to determine the evolutionary significance and potential adaptive advantages of this intron for the species.
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
(2021)
Article
Biochemistry & Molecular Biology
Tomoki Ueda, Kei-ichiro Nishimura, Yuka Nishiyama, Yuto Tominaga, Katsushi Miyazaki, Hiroyuki Furuta, Shigeyoshi Matsumura, Yoshiya Ikawa
Summary: Alternative splicing is an important mechanism in eukaryotic cells that allows multiple proteins to be produced from a single gene. Although it is usually associated with group I self-splicing introns, limited examples of alternative splicing have been reported. This study focuses on exon-skipping splicing in genes containing two group I introns and reveals the key structural elements important for this type of splicing through pairwise engineering and biochemical characterization.
Article
Microbiology
Masahiro C. Miura, Shohei Nagata, Satoshi Tamaki, Masaru Tomita, Akio Kanai
Summary: This study developed a bioinformatic pipeline to systematically collect and analyze Group II introns (G2Is) in prokaryotes. The results showed the presence of G2Is in both bacteria and archaea, with their numbers defined almost at the phylum level. Furthermore, a comprehensive sequence analysis led to the identification of three new categories of intron-encoded proteins (IEPs), and it was observed that about 30% of IEPs are non-canonical. The study also analyzed the relationship between genomic signatures and the mechanism of G2I increases.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Ecology
Felix LaRoche-Johnston, Catherine Prattico, Caroline Monat, Olivier Hinse, Benoit Cousineau
Summary: This study provides a comprehensive evolutionary history of a bacterial group II intron. It reveals that the Ll.LtrB homologs in Lactococci originated from a single lateral transfer event from Enterococcus faecalis. The study also demonstrates the dissemination of these introns in Lactococci through recurrent episodes of independent mobility events and lateral transfer.
Article
Plant Sciences
Leila Feiz, Yukari Asakura, Linyong Mao, Susan R. Strickler, Zhangjun Fei, Margarita Rojas, Alice Barkan, David B. Stern
Summary: A new study shows that CRM Family Member1 (CFM1) facilitates the splicing of chloroplast introns in plants, particularly those not previously known to require CRM domain proteins. Deficiencies in these introns result in compromised chloroplast protein synthesis, leading to whole-plant chlorotic phenotypes.
Review
Genetics & Heredity
Ron Mizrahi, Sofia Shevtsov-Tal, Oren Ostersetzer-Biran
Summary: Mitochondria are organelles responsible for cellular energy production. Plant mitochondria have introns that play a significant role in protein splicing. These splicing processes are regulated by various protein factors and may be associated with cellular and environmental signals.
Article
Biochemistry & Molecular Biology
Maria Dolores Molina-Sanchez, Fernando Manuel Garcia-Rodriguez, Eduardo Andres-Leon, Nicolas Toro
Summary: In this study, we investigated the binding sites of RmInt1 in the Sinorhizobium meliloti genome using chromatin-immunoprecipitation coupled with next-generation sequencing. Our results showed that RmInt1 binding sites mainly cluster around the replication origin of each replicon in the S. meliloti genome. This study provides new evidence linking the mobility of group II introns to host DNA replication.
FRONTIERS IN MOLECULAR BIOSCIENCES
(2022)
Article
Genetics & Heredity
Scout R. L. Thompson, Dong Kyung Lee, Marc-Andre Lachance, David Roy Smith
Summary: Studying homologous recombination with self-splicing introns in Metschnikowia yeasts' mitochondrial genomes sheds light on the mutational effects of these introns, revealing a higher density of polymorphisms near the insertion sites. This suggests that carrying self-splicing introns may come with fitness costs.
FRONTIERS IN GENETICS
(2021)
Article
Microbiology
Paula L. C. Fonseca, Ruth B. De-Paula, Daniel S. Araujo, Luiz Marcelo Ribeiro Tome, Thairine Mendes-Pereira, Wenderson Felipe Costa Rodrigues, Luiz-Eduardo Del-Bem, Eric R. G. R. Aguiar, Aristoteles Goes-Neto
Summary: The study found that fungal mitogenomes are diverse, contain accessory elements, and do not have a conserved gene that can be used for the taxonomic classification of fungi.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Biochemical Research Methods
Kok Zhi Lee, Michael A. Mechikoff, Mrugesh Krishna Parasa, Tyler J. Rankin, Paula Pandolfi, Kevin S. Fitzgerald, Ethan T. Hillman, Kevin Solomon
Summary: Prokaryote genomes encode diverse programmable DNA endonucleases with significant potential for biotechnology and gene editing. A positive selection screen based on the homing endonuclease I-SceI has been developed and validated to measure the relative activity of endonucleases and enrich for more active variants. This system may be applied in high throughput to characterize novel programmable endonucleases and evolve endonuclease function.
ACS SYNTHETIC BIOLOGY
(2022)
Article
Genetics & Heredity
Jennifer E. Hurtig, Ambro van Hoof
Summary: Through yeast genetics, it is discovered that TSEN not only participates in tRNA splicing but also has other functions, including degradation of a subset of mRNA encoding mitochondrial proteins and an unknown essential function. Overexpression of SEN54 can suppress sen2 mutants, indicating its general suppressive effect on sen2, regardless of tRNA-dependent or tRNA-independent functions. Mutations in the intron-debranching enzyme Dbr1 can also serve as tRNA splicing-independent suppressors. These findings provide insights into the essential function(s) of TSEN.
Article
Biochemistry & Molecular Biology
Li Zhang, Jingli Chen, Liqun Zhang, Ying Wei, Yajuan Li, Xinyun Xu, Hui Wu, Zhong-Nan Yang, Jirong Huang, Fenhong Hu, Weihua Huang, Yong-Lan Cui
Summary: The plastid-localized PPR protein EMB1270 is essential for chloroplast biogenesis in Arabidopsis thaliana, playing a crucial role in the accumulation of photosynthetic proteins and splicing efficiency of specific plastid introns. EMB1270 interacts with CFM2 to facilitate the splicing of group II introns, highlighting its importance in coordinating chloroplast and nuclear gene expression.
JOURNAL OF INTEGRATIVE PLANT BIOLOGY
(2021)
Article
Microbiology
Barney A. Geddes, Georg Hausner, Ivan J. Oresnik
Article
Mycology
Dipnath Baidyaroy, Georg Hausner, Helmut Bertrand
Article
Mycology
Mohamed Hafez, Mahmood Iranpour, Sahra-Taylor Mullineux, Jyothi Sethuraman, Kari M. Wosnitza, Paeta Lehn, Jennifer Kroeker, Peter C. Loewen, James Reid, Georg Hausner
Review
Biotechnology & Applied Microbiology
Mohamed Hafez, Georg Hausner
Article
Biochemistry & Molecular Biology
Sahra-Taylor Mullineux, Karla Willows, Georg Hausner
JOURNAL OF MOLECULAR EVOLUTION
(2011)
Article
Mycology
Mark Kowalski, Georg Hausner, Michele D. Piercey-Normore
Article
Mycology
Leonard J. Hutchison, Bradley R. Kropp, Georg Hausner
Article
Mycology
Shelly M. Rudski, Georg Hausner
Review
Biochemistry & Molecular Biology
Muntahi Mourin, Alvan Wai, Joe O'Neil, Georg Hausner, Pavel Dibrov
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2019)
Article
Infectious Diseases
Manu Singh, P. Malaka De Silva, Yasser Al-Saadi, Jacek Switala, Peter C. Loewen, Georg Hausner, Wangxue Chen, Ismael Hernandez, Santiago Castillo-Ramirez, Ayush Kumar
Article
Biochemistry & Molecular Biology
Christopher I. Graham, Palak G. Patel, Jennifer R. Tanner, Jacqueline Hellinga, Teassa L. MacMartin, Georg Hausner, Ann Karen C. Brassinga
Summary: PsrA in Legionella pneumophila is a host-specific requirement for optimal temporal progression of the intracellular lifecycle in A. castellanii, affecting bacterial intracellular growth and transmissive cyst formation.
MOLECULAR MICROBIOLOGY
(2021)
Article
Forestry
Hanna Stepniewska, Robert Jankowiak, Piotr Bilanski, Georg Hausner
Summary: Members of the genus Fusarium and related genera play important roles in many ecosystems worldwide, but their impact on the structure of beech litter communities and natural regeneration of European beech is not well understood. The study found that Fusarium species richness was highest in old-growth beech-dominated forests, while abundances were higher in managed beech stands, suggesting a potential negative impact on natural beech regeneration. Pathogenicity tests confirmed that certain Fusarium species isolated from beechnuts and beech germinants could cause rot, further supporting the hypothesis of their negative role in the natural regeneration of beech.
Review
Cell Biology
Jigeesha Mukhopadhyay, Georg Hausner
Summary: Introns in organellar genomes play important roles in encoding proteins and participating in non-canonical splicing. Different types of introns show diverse distribution patterns in fungi, plants, and algae.
Article
Biochemistry & Molecular Biology
Jigeesha Mukhopadhyay, Alvan Wai, Leonard J. Hutchison, Georg Hausner
Summary: This study investigates the mitochondrial genome of U. craterium, providing insights into the evolution of mitogenomes among members of the Pezizales in terms of gene content and order, mobile elements, and genome sizes.
CANADIAN JOURNAL OF MICROBIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Alvan Wai, Georg Hausner
Summary: Ceratocystiopsis is a fungal genus associated with bark beetles and other arthropods. The mitochondrial genome of Ceratocystiopsis pallidobrunnea is the smallest reported so far for this genus. The study found that gene arrangement is conserved in this group of fungi, and mitochondrial variation is largely due to the presence or absence of introns. The long-term goal is to use mitochondrial genomes to resolve taxonomic issues within the Ophiostomatales and Ophiostomataceae.
CANADIAN JOURNAL OF MICROBIOLOGY
(2022)