title: Underwater locomotion strategy by a benthic pennate diatom Navicula sp.
abstract: The mechanism of diatom locomotion has been widely researched but still remains a hypothesis. There are several questionable points on the prevailing model proposed by Edgar, and some of the observed phenomena cannot be completely explained by this model. In this paper, we undertook detailed investigations of cell structures, locomotion, secreted mucilage, and bending deformation for a benthic pennate diatom Navicula species. According to these broad evidences, an updated locomotion model is proposed. For Navicula sp., locomotion is realized via two or more pseudopods or stalks protruded out of the frustules. The adhesion can be produced due to the pull-off of one pseudopod or stalk from the substratum through extracellular polymeric substances. And the positive pressure is generated to balance the adhesion because of the push-down of another pseudopod or stalk onto the substratum. Because of the positive pressure, friction is generated, acting as a driving force of locomotion, and the other pseudopod or stalk can detach from the substratum, resulting in the locomotion. Furthermore, this model is validated by the force evaluation and can better explain observed phenomena. This updated model would provide a novel aspect on underwater locomotion strategy, hence can be useful in terms of artificial underwater locomotion devices.
authors: State Key Laboratory of Tribology, Tsinghua University, Beijing, 100084, People's Republic of China, jdwang@mail.tsinghua.edu.cn.
authors: Jiadao
authors: J
authors: Wang
authors: Shan
authors: S
authors: Cao
authors: Chuan
authors: C
authors: Du
authors: Darong
authors: D
authors: Chen
mesh_terms: D017377:Diatoms / Q000502:physiology*; D008124:Locomotion / Q000502:physiology
references: Cell Motil Cytoskeleton. 1999;44(1):23-33
references: 10470016
references: Nat Mater. 2003 Jul;2(7):461-3
references: 12776092
references: Biophys J. 2006 Apr 15;90(8):L58-60
references: 16500978
references: Biophys J. 2006 Apr 15;90(8):2987-93
references: 16443662
references: J R Soc Interface. 2008 Mar 6;5(20):383-5
references: 17848363
references: Biophys J. 2004 Dec;87(6):4284-97
references: 15377513
references: J Microbiol Methods. 2011 Dec;87(3):316-9
references: 21963449
references: Nature. 2000 Jun 8;405(6787):681-5
references: 10864324
references: Protist. 2002 Mar;153(1):25-38
references: 12022272
references: Proc Natl Acad Sci U S A. 2005 Nov 8;102(45):16293-6
references: 16260737
references: Biofouling. 2008;24(5):365-79
references: 18604655
references: Exp Cell Res. 1973 Aug;80(2):490-3
references: 4200833
references: Photosynth Res. 1983 Dec;4(4):361-73
references: 24458529
references: Protist. 1999 Mar;150(1):25-32
references: 10724516
references: J Mol Recognit. 2011 May-Jun;24(3):436-45
references: 21504021
references: Planta. 1997 Oct;203(2):213-21
references: 9362567