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Directional bleb formation in spherical cells under temperature gradient.

ABSTRACT: Living cells sense absolute temperature and temporal changes in temperature using biological thermosensors such as ion channels. Here, we reveal, to our knowledge, a novel mechanism of sensing spatial temperature gradients within single cells. Spherical mitotic cells form directional membrane extensions (polar blebs) under sharp temperature gradients (??0.065°C ?m(-1); 1.3°C temperature difference within a cell), which are created by local heating with a focused 1455-nm laser beam under an optical microscope. On the other hand, multiple nondirectional blebs are formed under gradual temperature gradients or uniform heating. During heating, the distribution of actomyosin complexes becomes inhomogeneous due to a break in the symmetry of its contractile force, highlighting the role of the actomyosin complex as a sensor of local temperature gradients.

SUBMITTER: Oyama K

PROVIDER: S-EPMC4621819 | biostudies-other | 2015 Jul

REPOSITORIES: biostudies-other

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Directional bleb formation in spherical cells under temperature gradient.

Oyama Kotaro K Arai Tomomi T Isaka Akira A Sekiguchi Taku T Itoh Hideki H Seto Yusuke Y Miyazaki Makito M Itabashi Takeshi T Ohki Takashi T Suzuki Madoka M Ishiwata Shin'ichi S

Biophysical journal 20150701 2

Living cells sense absolute temperature and temporal changes in temperature using biological thermosensors such as ion channels. Here, we reveal, to our knowledge, a novel mechanism of sensing spatial temperature gradients within single cells. Spherical mitotic cells form directional membrane extensions (polar blebs) under sharp temperature gradients (≥∼0.065°C μm(-1); 1.3°C temperature difference within a cell), which are created by local heating with a focused 1455-nm laser beam under an optic ...[more]

PMID: 26200871

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