The contracted and prolonged states of Spirostomum cells. Chinese scientists have found the molecular foundation for the ultrafast contraction of Spirostomum, a genus of millimeter-scale single-celled protists recognized for his or her extremely fast motion, utilizing a high-quality genome obtained from RNAi. Credit: Image by IHB
Scientists have found the molecular foundation for the ultrafast contraction of Spirostomum, a genus of millimeter-scale single-celled protists recognized for his or her extremely fast motion. Using a high-quality genome obtained from RNAi, the researchers discovered that the contractile construction, a mesh-like contractile fibrillar system, was composed of two large proteins and two Ca2+ binding proteins. This research is important for understanding the molecular mechanism of ultrafast cell contraction and offers a blueprint for the design and development of ultrafast contractile micromachines.
In his well-known letter to the Royal Society dated October 9, 1676, Antonie van Leeuwenhoek described a single-celled eukaryote (Vorticella) and its fascinating ultrafast cell contraction as the primary set of discoveries. This type of ultrafast cell contraction triggered by a Ca2+-dependent mechanism is distinct from the adenosine triphosphate (ATP)-dependent mechanisms present in actin-myosin and dynein/kinesin-tubulin programs.
Spirostomum, is a genus of millimeter-scale single-celled protists which can be recognized for his or her extremely fast motion like Vorticella. They are able to among the quickest motion within the organic world because of their ultrafast contraction. Despite a lot analysis, nonetheless, the molecular mechanism behind the sort of ultrafast cell contraction has lengthy been a thriller.
Recently, a analysis group led by Prof. MIAO Wei from the Institute of Hydrobiology (IHB) of the Chinese Academy of Sciences has unlocked this thriller by describing the molecular foundation behind the ultrafast contraction of Spirostomum. The staff’s analysis was revealed in Science Advances.
In this study, the researchers obtained a high-quality genome of Spirostomum using a genome assembly pipeline they had previously established. They found that the contractile structure, a mesh-like contractile fibrillar system, was composed of two giant proteins and two Ca2+ binding proteins. Using RNAi, they validated the functions of the giant proteins.
Super-resolution imaging showed that the mesh-like contractile fibrillar system couples with the microtube cytoskeleton, mitochondria and endoplasmic reticulum (ER) and fits well with the biological and physical need for repetitive ultrafast contraction and extension of the Spirostomum cell.
“Actually, our research offers a valuable reference for investigating non-model protists, covering aspects from the genome to molecular studies,” said Prof. MIAO.
This study is highly significant for understanding the molecular mechanism of ultrafast cell contraction and provides a good blueprint for the biomimicry, design, and construction of ultrafast contractile micromachines.
Reference: “Giant proteins in a giant cell: Molecular basis of ultrafast Ca2+-dependent cell contraction” by Jing Zhang, Weiwei Qin, Che Hu, Siyu Gu, Xiaocui Chai, Mingkun Yang, Fang Zhou, Xueyan Wang, Kai Chen, Guanxiong Yan, Guangying Wang, Chuanqi Jiang, Alan Warren, Jie Xiong and Wei Miao, 22 February 2023, Science Advances.
DOI: 10.1126/sciadv.add6550
