AI Article Synopsis
- Little is known about how organelle size is regulated in cells, but the study identifies a new cyclin-dependent kinase (CDK) called LF2, essential for controlling flagellar length in Chlamydomonas reinhardtii.
- The LF2 protein lacks a typical cyclin-binding motif but retains crucial kinase activity residues, and mutations in the LF2 gene affect flagellar length and assembly.
- LF2p interacts with other flagellar proteins (LF1p and LF3p), suggesting it plays a key role in a regulatory kinase complex that governs the assembly and length of flagella.
Article Abstract
Little is known about how cells regulate the size of their organelles. In this study, we find that proper flagellar length control in Chlamydomonas reinhardtii requires the activity of a new member of the cyclin-dependent kinase (CDK) family, which is encoded by the LF2 (long flagella 2) gene. This novel CDK contains all of the important residues that are essential for kinase activity but lacks the cyclin-binding motif PSTAIRE. Analysis of genetic lesions in a series of lf2 mutant alleles and site-directed mutagenesis of LF2p reveals that improper flagellar length and defective flagellar assembly correlate with the extent of disruption of conserved kinase structures or residues by mutations. LF2p appears to interact with both LF1p and LF3p in the cytoplasm, as indicated by immunofluorescence localization, sucrose density gradients, cell fractionation, and yeast two-hybrid experiments. We propose that LF2p is the catalytic subunit of a regulatory kinase complex that controls flagellar length and flagellar assembly.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2064056 | PMC |
| http://dx.doi.org/10.1083/jcb.200610022 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Flagellum Pumping Efficiency in Shear-Thinning Viscoelastic Fluids.
J Fluid Mech
November 2024
Department of Mathematics, University of North Carolina, Chapel Hill, NC, USA.
Microorganism motility often takes place within complex, viscoelastic fluid environments, e.g., sperm in cervicovaginal mucus and bacteria in biofilms.
View Article and Find Full Text PDFFlaG competes with FliS-flagellin complexes for access to FlhA in the flagellar T3SS to control filament length.
Proc Natl Acad Sci U S A
October 2024
Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9048.
Article Synopsis
- Bacteria use a structure called a flagellar filament, made of many subunits, to swim, but it's unclear how they control its length.
- Deleting certain genes in polar flagellated bacteria resulted in longer flagellar filaments, suggesting that the FlaG protein helps regulate filament length by interfering with another protein, FliS, in the secretion system.
- Both flagellar filaments and injectisome systems appear to have evolved similar protein mechanisms to control the secretion of crucial components, highlighting a convergence in bacterial adaptation strategies.
The Structure of Cilium Inner Junctions Revealed by Electron Cryo-tomography.
bioRxiv
September 2024
Department of Molecular and Cellular Biology, University of California Davis, Davis, CA 95616, USA.
The cilium is a microtubule-based organelle critical for many cellular functions. Its assembly initiates at a basal body and continues as an axoneme that projects out of the cell to form a functional cilium. This assembly process is tightly regulated.
View Article and Find Full Text PDFMotile bacteria crossing liquid-liquid interfaces of an aqueous isotropic-nematic coexistence phase.
Soft Matter
September 2024
Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
In nature, bacteria often swim in complex fluids, but our understanding of the interactions between bacteria and complex surroundings is still evolving. In this work, rod-like swims in a quasi-2D environment with aqueous liquid-liquid interfaces, , the isotropic-nematic coexistence phase of an aqueous chromonic liquid crystal. Focusing on the bacteria motion near and at the liquid-liquid interfaces, we collect and quantify bacterial trajectories ranging across the isotropic to the nematic phase.
View Article and Find Full Text PDFPhylogeny and ultrastructure of a non-toxigenic dinoflagellate Amphidoma fulgens sp. nov. (Amphidomataceae, Dinophyceae), with a wide distribution across Asian Pacific.
Harmful Algae
September 2024
Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan. Electronic address:
Article Synopsis
- Amphidoma languida, a dinoflagellate known for producing the toxin azaspiracids, has been detected in environmental DNA in the Asia Pacific, despite no confirmed sightings.
- The study examined the morphology, ultrastructure, and phylogeny of nine recently isolated strains of Amphidoma from Japan, Malaysia, and the Philippines, revealing differences from the Atlantic species.
- Findings indicate that these Pacific strains, proposed as a new species named Amphidoma fulgens sp. nov., are non-toxigenic and display unique structural features compared to Am. languida.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!