Article
Biochemistry & Molecular Biology
Shimi Meleppattu, Haixia Zhou, Jin Dai, Miao Gui, Alan Brown
Summary: This study determined the structures of native IFT-A complexes using cryo-EM and found that subcomplex rearrangements enable IFT-A to polymerize on anterograde IFT trains. The study also discovered that binding of IFT-A to IFT-B shields the preferred lipid-binding interface and orients a network of b-propeller domains towards the ciliary membrane, capable of accommodating diverse cargoes.
Article
Biology
Hiroaki Ishikawa, Jeremy Moore, Dennis R. Diener, Markus Delling, Wallace F. Marshall, Lotte B. Pedersen
Summary: This study investigates the length regulation of flagella and its impact on carrier transport. Although the concentration of calcium ions inside the flagella is weakly correlated with flagellar length, experiments demonstrate that calcium ions do not serve as the basis for a stable length control system.
Article
Genetics & Heredity
Limei Wang, Xuecheng Li, Guang Liu, Junmin Pan
Summary: FBB18 plays a crucial role in the assembly of dynein arms by facilitating the folding/stabilization of almost all axonemal dyneins. Mutations in FBB18 result in short or absent cilia with partial loss of dynein arms. FBB18 interacts with multiple DNAAFs simultaneously, indicating the importance of dynein folding/stability in axonemal dynein preassembly.
Article
Biochemistry & Molecular Biology
Xin Zhu, Jieling Wang, Shufen Li, Karl Lechtreck, Junmin Pan
Summary: This study revealed that the IFT-B protein IFT54 interacts with both kinesin-II and IFT dynein, regulating anterograde transport. Deletions of specific residues in IFT54 resulted in disrupted anterograde trafficking of IFT, with accumulations of IFT motors and complexes in different regions of cilia. This suggests a central role for IFT54 in binding IFT motors during anterograde transport.
Article
Multidisciplinary Sciences
Jieling Wang, Xin Zhu, Zhengmao Wang, Xuecheng Li, Hui Tao, Junmin Pan
Summary: The machinery of intraflagellar transport (IFT) consists of IFT motors and cargo adaptors, including IFT-A and IFT-B complexes. This study reveals the role of IFT38 in the regulation of anterograde IFT and retrograde trafficking of BBSome. The stability of IFT-B1 and IFT-B2 is mutually dependent and mediated by the connecting tetramer IFT38/5788/52. The findings suggest a modular pathway for IFT-B assembly.
Review
Cell Biology
Nikolai Klena, Gaia Pigino
Summary: Cilia are eukaryotic organelles that play a crucial role in cell motility and signaling. Recent advances in cryo-electron tomography and single-particle analysis cryo-electron microscopy have provided important insights into the structure and function of cilia.
ANNUAL REVIEW OF CELL AND DEVELOPMENTAL BIOLOGY
(2022)
Article
Microbiology
Reid T. Oshiro, Caroline M. Dunn, Daniel B. Kearns
Summary: CsrA is an RNA-binding protein acting as a posttranscriptional regulator in bacteria, inhibited competitively by small RNAs in gammaproteobacteria and non-competitively by a protein inhibitor FliW in firmicute Bacillus subtilis. Study reveals that FliW inhibition of CsrA relies on the disruption of a salt bridge near the core of the CsrA dimer, suggesting an allosteric mechanism for abolishing RNA-binding activity.
JOURNAL OF BACTERIOLOGY
(2021)
Article
Multidisciplinary Sciences
Wenjuan Wang, Jinqi Ren, Weiye Song, Yong Zhang, Wei Feng
Summary: This study reveals the autoinhibition mechanism of kinesin-3 KLP6, in which the internal coiled-coil segments and domains cooperate to lock down the neck and motor domains, ensuring proper spatiotemporal control of intracellular transport.
NATURE COMMUNICATIONS
(2022)
Review
Biochemistry & Molecular Biology
Shuichi Nakamura
Summary: The ability of bacteria to move is crucial for their survival and can be a virulence factor for pathogenic species. This review focuses on the significance of motility, particularly crawling, in liquid and on surfaces, for the causative agent of zoonosis leptospirosis.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Cell Biology
Meiqin Jiang, Vivek Reddy Palicharla, Darcie Miller, Sun-Hee Hwang, Hanwen Zhu, Patricia Hixson, Saikat Mukhopadhyay, Ji Sun
Summary: This study reports the cryo-EM structures of human IFT-A complexes, revealing their lariat shape and vital zinc-binding domains. The cargo adapter TULP3 interacts with IFT-A through its N-terminal region, and mutations disrupt cargo transport. These findings provide insights into the structure and function of IFT-A, ciliary transport, and disease mutations.
Article
Biochemistry & Molecular Biology
Alina Guse, Manuel Halte, Svenja Huesing, Marc Erhardt
Summary: The study revealed that the type-III secretion system of bacterial flagellum has a remarkable substrate specificity during flagellar assembly, accurately secreting the required substrates at different stages, and the specificity switch is unidirectional and irreversible.
MOLECULAR MICROBIOLOGY
(2021)
Review
Cell Biology
Karl Lechtreck
Summary: The assembly and maintenance of cilia and eukaryotic flagella rely on intraflagellar transport (IFT), which involves the movement of IFT trains along microtubules. Adapters are used to transport ciliary proteins and complexes between the cell body and the organelle. These adapters expand the cargo range of IFT trains.
JOURNAL OF CELL SCIENCE
(2022)
Article
Microbiology
Sandra Sanchez, Elizabeth Snider, Xindan Wang, Daniel B. Kearns
Summary: Using TnSeq, researchers identified new genes involved in swarming motility of Bacillus subtilis. The study confirmed the known genes required for flagellar biosynthesis and regulators that promote swarming, and also discovered additional genes that enhance swarming. The results demonstrate the power of TnSeq for genetic analysis of nonessential processes and provide insights into the mechanism of swarming in B. subtilis.
JOURNAL OF BACTERIOLOGY
(2022)
Article
Developmental Biology
Hiroyuki Yamaguchi, Megumi Kitami, Karin H. Uchima Koecklin, Li He, Jianbo Wang, William R. Lagor, Daniel S. Perrien, Yoshihiro Komatsu
Summary: This study reveals the importance of IFT20 in endochondral ossification in mice. IFT20 regulates FGF signaling to promote chondrogenesis. Loss of IFT20 results in shortened limb outgrowth and absence of primary cilia on chondrocytes.
DEVELOPMENTAL BIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Adeline Mallet, Philippe Bastin
Summary: Cilia are unique eukaryotic organelles that show remarkable conservation during evolution. Recent studies have found that intraflagellar transport (IFT) trains, which are responsible for cilia assembly, are restricted to certain doublet microtubules. This restricted positioning of IFT trains may play a role in the evolution of cilia towards more complex or simpler configurations.