scholarly journals Phylogenetic profiling and cellular analyses of ARL16 reveal roles in traffic of IFT140 and INPP5E

2021 ◽  
Author(s):  
Skylar I Dewees ◽  
Romana Vargova ◽  
Katherine R Hardin ◽  
Rachel E Turn ◽  
Saroja Devi ◽  
...  
Keyword(s):  
Protein Content ◽  
Common Ancestor ◽  
Family Members ◽  
Last Eukaryotic Common Ancestor ◽  
Core Component ◽  
Cell Functions ◽  
Diverse Species ◽  
Ciliary Protein ◽  
Phylogenetic Profiling

The ARF family of regulatory GTPases is ancient, with 16 members predicted to have been present in the last eukaryotic common ancestor. Our phylogenetic profiling of paralogs in diverse species identified four family members whose presence correlates with that of a cilium/flagellum: ARL3, ARL6, ARL13, and ARL16. No prior evidence links ARL16 to cilia or other cell functions, despite its presence throughout eukaryotes. Deletion of ARL16 in MEFs results in decreased ciliogenesis yet increased ciliary length. We also found Arl16 KO in MEFs to alter ciliary protein content, including loss of ARL13B, ARL3, INPP5E, and the IFT-A core component IFT140. Instead, both INPP5E and IFT140 accumulate at the Golgi in Arl16 KO lines, while other IFT proteins do not, suggesting a specific defect in traffic from Golgi to cilia. We propose that ARL16 regulates a Golgi-cilia traffic pathway and is required specifically in the export of IFT140 and INPP5E from the Golgi.

scholarly journals Germline Transformation of Drosophila virilis With the Transposable Element mariner

Genetics ◽  
1996 ◽  
Vol 143 (1) ◽  
pp. 365-374 ◽  
Author(s):  
Allan R Lohe ◽  
Daniel L Hartl
Keyword(s):  
Transposable Element ◽  
Common Ancestor ◽  
Pcr Amplification ◽  
Drosophila Virilis ◽  
Cell Region ◽  
Diverse Species ◽  
Drosophila Mauritiana ◽  
Characteristic 2 ◽  
In Situ Hybridizations

Abstract An important goal in molecular genetics has been to identify a transposable element that might serve as an efficient transformation vector in diverse species of insects. The transposable element mariner occurs naturally in a wide variety of insects. Although virtually all mariner elements are nonfunctional, the Mosl element isolated from Drosophila mauritiana is functional. Mosl was injected into the pole-cell region of embryos of D. virilis, which last shared a common ancestor with D. mauritiana 40 million years ago. Mosl PCR fragments were detected in several pools of DNA from progeny of injected animals, and backcross lines were established. Because Go lines were pooled, possibly only one transformation event was actually obtained, yielding a minimum frequency of 4%. Mosl segregated in a Mendelian fashion, demonstrating chromosomal integration. The copy number increased by spontaneous mobilization. In situ hybridization confirmed multiple polymorphic locations of Mosl. Integration results in a characteristic 2-bp TA duplication. One Mosl element integrated into a tandem array of 370-bp repeats. Some copies may have integrated into heterochromatin, as evidenced by their ability to support PCR amplification despite absence of a signal in Southern and in situ hybridizations.

Protein folding in the cell: functions of two families of molecular chaperone, hsp 60 and TF55-TCP1

1993 ◽  
Vol 339 (1289) ◽  
pp. 313-326 ◽  
Keyword(s):  
Protein Folding ◽  
Mechanism Of Action ◽  
Molecular Chaperone ◽  
Polypeptide Chain ◽  
Family Members ◽  
Chain Folding ◽  
Cell Functions ◽  
Cellular Compartments

Two families of molecular chaperone, the hsp 60-GroEL family and the TF55-TCP1 family, have been discovered in evolutionarily related cellular compartments. A member of one of these families, hsp 60, has been shown to play a global role in polypeptide chain folding in mitochondria. We review here studies of both hsp 60 and other family members, discussing their essential physiological roles and mechanism of action.

scholarly journals Structural characterization of a Thorarchaeota profilin indicates eukaryotic-like features but with an extended N-terminus

2021 ◽  
Author(s):  
Celestine N Chi ◽  
Ravi Teja Inturi ◽  
Sandra Martinez Lara ◽  
Mahmoud Darweesh
Keyword(s):  
Common Ancestor ◽  
Three Dimensional ◽  
Eukaryotic Cell ◽  
Dimensional Structure ◽  
Resonance Spectroscopy ◽  
Last Eukaryotic Common Ancestor ◽  
Rigid Core ◽  
N Terminus ◽  
Metagenomics Analysis

The emergence of the first eukaryotic cell was preceded by evolutionary events which are still highly debatable. Recently, comprehensive metagenomics analysis has uncovered that the Asgard super-phylum is the closest yet known archaea host of eukaryotes. However, it remains to be established if a large number of eukaryotic signature proteins predicated to be encoded by the Asgard super-phylum are functional at least, in the context of a eukaryotic cell. Here, we determined the three-dimensional structure of profilin from Thorarchaeota by nuclear magnetic resonance spectroscopy and show that this profilin has a rigid core with a flexible N-terminus which was previously implicated in polyproline binding. In addition, we also show that thorProfilin co-localizes with eukaryotic actin in cultured HeLa cells. This finding reaffirm the notion that Asgardean encoded proteins possess eukaryotic-like characteristics and strengthen likely existence of a complex cytoskeleton already in a last eukaryotic common ancestor

scholarly journals Ancient dynamin segments capture early stages of host–mitochondrial integration

2015 ◽  
Vol 112 (9) ◽  
pp. 2800-2805 ◽  
Author(s):  
Ramya Purkanti ◽  
Mukund Thattai
Keyword(s):  
Functional Data ◽  
Common Ancestor ◽  
Structural Elements ◽  
Last Eukaryotic Common Ancestor ◽  
Mitochondrial Division ◽  
Deep Time ◽  
Extant Species ◽  
Sequence Reconstruction ◽  
Secondary Structural Elements ◽  
Phylogenetic Method

Eukaryotic cells use dynamins—mechano-chemical GTPases—to drive the division of endosymbiotic organelles. Here we probe early steps of mitochondrial and chloroplast endosymbiosis by tracing the evolution of dynamins. We develop a parsimony-based phylogenetic method for protein sequence reconstruction, with deep time resolution. Using this, we demonstrate that dynamins diversify through the punctuated transformation of sequence segments on the scale of secondary-structural elements. We find examples of segments that have remained essentially unchanged from the 1.8-billion-y-old last eukaryotic common ancestor to the present day. Stitching these together, we reconstruct three ancestral dynamins: The first is nearly identical to the ubiquitous mitochondrial division dynamins of extant eukaryotes, the second is partially preserved in the myxovirus-resistance-like dynamins of metazoans, and the third gives rise to the cytokinetic dynamins of amoebozoans and plants and to chloroplast division dynamins. The reconstructed sequences, combined with evolutionary models and published functional data, suggest that the ancestral mitochondrial division dynamin also mediated vesicle scission. This bifunctional protein duplicated into specialized mitochondrial and vesicle variants at least three independent times—in alveolates, green algae, and the ancestor of fungi and metazoans—accompanied by the loss of the ancient prokaryotic mitochondrial division protein FtsZ. Remarkably, many extant species that retain FtsZ also retain the predicted ancestral bifunctional dynamin. The mitochondrial division apparatus of such organisms, including amoebozoans, red algae, and stramenopiles, seems preserved in a near-primordial form.

scholarly journals Syntaxin-17 delivers PINK1/parkin-dependent mitochondrial vesicles to the endolysosomal system

2016 ◽  
Vol 214 (3) ◽  
pp. 275-291 ◽  
Author(s):  
Gian-Luca McLelland ◽  
Sydney A. Lee ◽  
Heidi M. McBride ◽  
Edward A. Fon
Keyword(s):  
Common Ancestor ◽  
Vesicle Transport ◽  
Late Endosome ◽  
Snare Complex ◽  
Endomembrane System ◽  
Last Eukaryotic Common Ancestor ◽  
Transport Pathway ◽  
Attachment Protein ◽  
Mitochondrial Content ◽  
Protein Receptor

Mitochondria are considered autonomous organelles, physically separated from endocytic and biosynthetic pathways. However, recent work uncovered a PINK1/parkin-dependent vesicle transport pathway wherein oxidized or damaged mitochondrial content are selectively delivered to the late endosome/lysosome for degradation, providing evidence that mitochondria are indeed integrated within the endomembrane system. Given that mitochondria have not been shown to use canonical soluble NSF attachment protein receptor (SNARE) machinery for fusion, the mechanism by which mitochondrial-derived vesicles (MDVs) are targeted to the endosomal compartment has remained unclear. In this study, we identify syntaxin-17 as a core mitochondrial SNARE required for the delivery of stress-induced PINK1/parkin-dependent MDVs to the late endosome/lysosome. Syntaxin-17 remains associated with mature MDVs and forms a ternary SNARE complex with SNAP29 and VAMP7 to mediate MDV–endolysosome fusion in a manner dependent on the homotypic fusion and vacuole protein sorting (HOPS) tethering complex. Syntaxin-17 can be traced to the last eukaryotic common ancestor, hinting that the removal of damaged mitochondrial content may represent one of the earliest vesicle transport routes in the cell.

scholarly journals Molecular paleontology and complexity in the last eukaryotic common ancestor

2013 ◽  
Vol 48 (4) ◽  
pp. 373-396 ◽  
Author(s):  
V. Lila Koumandou ◽  
Bill Wickstead ◽  
Michael L. Ginger ◽  
Mark van der Giezen ◽  
Joel B. Dacks ◽  
...  
Keyword(s):  
Common Ancestor ◽  
Last Eukaryotic Common Ancestor ◽  
Molecular Paleontology

scholarly journals What can we infer about the origin of sex in early eukaryotes?

2016 ◽  
Vol 371 (1706) ◽  
pp. 20150530 ◽  
Author(s):  
Dave Speijer
Keyword(s):  
Large Scale ◽  
Common Ancestor ◽  
Previous Analysis ◽  
Oxygen Species ◽  
Mitochondrial Inheritance ◽  
Last Eukaryotic Common Ancestor ◽  
Current Analysis ◽  
Flexible Form ◽  
Organellar Dna ◽  
Stress Signals

Current analysis shows that the last eukaryotic common ancestor (LECA) was capable of full meiotic sex. The original eukaryotic life cycle can probably be described as clonal, interrupted by episodic sex triggered by external or internal stressors. The cycle could have started in a highly flexible form, with the interruption of either diploid or haploid clonal growth determined by stress signals only. Eukaryotic sex most likely evolved in response to a high mutation rate, arising from the uptake of the endosymbiont, as this (proto) mitochondrion generated internal reactive oxygen species. This is consistent with the likely development of full meiotic sex from a diverse set of existing archaeal (the host of the endosymbiont) repair and signalling mechanisms. Meiotic sex could thus have been one of the fruits of symbiogenesis at the basis of eukaryotic origins: a product of the merger by which eukaryotic cells arose. Symbiogenesis also explains the large-scale migration of organellar DNA to the nucleus. I also discuss aspects of uniparental mitochondrial inheritance and mitonuclear interactions in the light of the previous analysis. This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.

scholarly journals Subcompartmentalization and pseudo-division of model protocells

2020 ◽  
Author(s):  
Karolina Spustova ◽  
Elif Senem Köksal ◽  
Alar Ainla ◽  
Irep Gözen
Keyword(s):  
Energy Supply ◽  
Common Ancestor ◽  
Experimental Studies ◽  
Chemical Energy ◽  
Early Earth ◽  
Last Eukaryotic Common Ancestor ◽  
Last Universal Common Ancestor ◽  
Materials Properties ◽  
Universal Common Ancestor ◽  
Intracellular Compartments

Membrane enclosed intracellular compartments have been exclusively associated with the eukaryotes, represented by the highly compartmentalized last eukaryotic common ancestor. Recent evidence showing the presence of membranous compartments with specific functions in archaea and bacteria makes it conceivable that the last universal common ancestor and its hypothetical precursor, the protocell, could have exhibited compartmentalization. To our knowledge, there are no experimental studies yet that have tested this hypothesis. We report on an autonomous subcompartmentalization mechanism for protocells which results in the transformation of initial subcompartments to daughter protocells. The process is solely determined by the fundamental materials properties and interfacial events, and do not require biological machinery or chemical energy supply. In the light of our findings, we propose that similar events could have taken place under early Earth conditions, leading to the development of compartmentalized cells and potentially, primitive division.

scholarly journals The evolution and diversity of the nonsense-mediated mRNA decay pathway

F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 1299 ◽  
Author(s):  
James P. B. Lloyd
Keyword(s):  
Alternative Splicing ◽  
Stress Response ◽  
Driving Force ◽  
Mrna Decay ◽  
Common Ancestor ◽  
Last Eukaryotic Common Ancestor ◽  
Eukaryotic Evolution ◽  
Premature Termination Codons ◽  
Upstream Orf ◽  
Nonsense Mediated Mrna Decay

Nonsense-mediated mRNA decay is a eukaryotic pathway that degrades transcripts with premature termination codons (PTCs). In most eukaryotes, thousands of transcripts are degraded by NMD, including many important regulators of development and stress response pathways. Transcripts can be targeted to NMD by the presence of an upstream ORF or by introduction of a PTC through alternative splicing. Many factors involved in the recognition of PTCs and the destruction of NMD targets have been characterized. While some are highly conserved, others have been repeatedly lost in eukaryotic lineages. Here, I outline the factors involved in NMD, our current understanding of their interactions and how they have evolved. I outline a classification system to describe NMD pathways based on the presence/absence of key NMD factors. These types of NMD pathways exist in multiple different lineages, indicating the plasticity of the NMD pathway through recurrent losses of NMD factors during eukaryotic evolution. By classifying the NMD pathways in this way, gaps in our understanding are revealed, even within well studied organisms. Finally, I discuss the likely driving force behind the origins of the NMD pathway before the appearance of the last eukaryotic common ancestor: transposable element expansion and the consequential origin of introns.

Sign in / Sign up

Export Citation Format

Share Document