@conference{
author = "Pajić, Tanja and Kozakijević, Suzana and Krmpot, Aleksandar J. and Živić, Miroslav and Todorović, Nataša and Rabasović, Mihailo D.",
year = "2023",
abstract = "Mitochondrial function, and consequently cellular metabolic status and fitness of a cell, is tightly linked
to the dynamic changes of mitochondrial morphology, including mitochondrial fusion, fission and
mitophagy [1]. Lipid droplets (LDs) can be in close contact with mitochondria, and accumulate
autophagy or mitophagy generated material during the reparatory processes [2]. The effect of increased
ambient temperature on mitochondrial morphology and LDs density in living cells of the filamentous
fungus Phycomyces blakesleeanus was investigated. For in vivo imaging of mitochondria and LDs
multiphoton microscopy was used. Multiphoton microscopy enables 3D imaging in high resolution and
reduced photodamage and photobleaching of the sample using IR ultrafast pulsed lasers. Mitochondria
were stained with the vital dye Rhodamine123 (Rh123) which enters these organelles based on their
membrane potential - mitochondria must be healthy/active to stain. A wavelength of 800 nm from Ti:Sa
laser (160 fs pulse duration, 76 MHz repetition rate) was used for two-photon excitation of Rh123. The
laser beam was focused by the Zeiss Plan Neofluar 40x1.3 objective lens and the signal was detected
through a bandpass interference filter MF530/43 (ThorLabs, USA). For LDs staining a Nile Red dye
was used and excited by Yb: KGW laser at 1040 nm [3]. Six morphological types of mitochondria were
observed in the hyphae of this fungus: intermediate type - normal, intermediate with small semicircular
tubules, tubular, elongated tubular, fragmented (small ellipsoid tubule) and fragmented with exclusively
spheroid-shaped mitochondria. Changes in mitochondrial morphology were induced by a small
temperature change. A 3°C increase in ambient temperature, from 22°C, had a dramatic effect on
mitochondrial morphology, inducing the appearance of a predominantly tubular mitochondrial
morphology. The total area percentage of mitochondria showed an increasing trend when grown at
25°C. Increasing the ambient temperature to 25°C induced a statistically significant increase in the
percentage of hyphal area occupied by LDs from 2.9 ± 1.6 to 4.7 ± 2.2 (mean value and SD in percentage
of hyphal area). The observed response to the small temperature increase points to the physiological
adaptation of hyphal metabolism.",
publisher = "Belgrade: Vinča Institute of Nuclear Sciences – National Institute of the Republic of Serbia, University of Belgrade",
journal = "Book of abstracts: 9th International School and Conference on Photonics PHOTONICA 2023 with joint events: Understanding interaction light - biological surfaces possibility for new electronic materials and devices and Biological and bioinspired structures for multispectral surveillance and Quantum sensing integration within microfluidic Lab-on-a Chips for biomedical applications; 2023 Aug 28 - Sep 01; Belgrade, Serbia",
title = "In vivo multiphoton imaging of a filamentous fungus Phycomyces blakesleeanus: the effect of small ambient temperature increase on mitochondrial morphology and lipid droplets density",
pages = "84",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_6249"
}
