liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Height changes associated with pigment aggregation in Xenopus laevis melanophores
Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
Show others and affiliations
2004 (English)In: Bioscience Reports, ISSN 0144-8463, E-ISSN 1573-4935, Vol. 24, no 3, 203-214 p.Article in journal (Refereed) Published
Abstract [en]

Melanophores are pigment cells found in the skin of lower vertebrates. The brownish-black pigment melanin is stored in organelles called melanosomes. In response to different stimuli, the cells can redistribute the melanosomes, and thereby change colour. During melanosome aggregation, a height increase has been observed in fish and frog melanophores across the cell centre. The mechanism by which the cell increases its height is unknown. Changes in cell shape can alter the electrical properties of the cell, and thereby be detected in impedance measurements. We have in earlier studies of Xenopus laevis melanophores shown that pigment aggregation can be revealed as impedance changes, and therefore we were interested in investigating the height changes associated with pigment aggregation further. Accordingly, we quantified the changes in cell height by performing vertical sectioning with confocal microscopy. In analogy with theories explaining the leading edge of migrating cells, we investigated the possibility that the elevation of plasma membrane is caused by local swelling due to influx of water through HgC12-sensitive aquaporins. We also measured the height of the microtubule structures to assess whether they are involved in the height increase. Our results show that pigment aggregation in X. laevis melanophores resulted in a significant height increase, which was substantially larger when aggregation was induced by latrunculin than with melatonin. Moreover, the elevation of the plasma membrane did not correlate with influx of water through aquaporins or formation of new microtubules, Rather, the accumulation of granules seemed to drive the change in cell height.

Place, publisher, year, edition, pages
2004. Vol. 24, no 3, 203-214 p.
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:liu:diva-31125DOI: 10.1007/s10540-005-2581-6PubMedID: 16209129Local ID: 16859OAI: oai:DiVA.org:liu-31125DiVA: diva2:251948
Available from: 2009-10-09 Created: 2009-10-09 Last updated: 2017-12-13Bibliographically approved
In thesis
1. Biophysical studies of pigment transport in frog melanophores: impedance measurements and advanced microscopy analyses
Open this publication in new window or tab >>Biophysical studies of pigment transport in frog melanophores: impedance measurements and advanced microscopy analyses
2003 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Small proteins, other molecules and large organelles are frequently transported from one location to another within cells. These transports employ cytoskeletal networks and enable cells to maintain regions with different functions and attain an asymmetrical shape.

The aim of this work was to explore biophysical methods for monitoring intracellular transport processes and associated structural changes. For these studies we have used pigment cells, melanophores, from the African clawed frog Xenopus laevis. In response to external stimuli, these cells can change colour by redistributing pigment granules in the cytoplasm.

Transparent "cell clinics" equipped with gold electrodes were developed for impedance studies. The results show that impedance measurements at different frequencies not only can be used to monitor cell attachment and spreading, but also events like pigment aggregation. Significant F-actin breakdown and a cell area decrease may explain the impedance decrease seen during latrunculin-induced aggregation. In aggregation induced by melatonin there was, however, a small increase of the cell area, no F-actin breakdown and still lowered impedance, indicating that some other, likely intracellular mechanism is involved. In addition, confocal laser scanning microscopy (CLSM) studies showed that aggregation was associated with an increase in the cell height, more prominent for latrunculin than for melatonin. This height increase did not seem to involve influx of water through aquaporin channels at the cell membrane, or newly formed or remodelled microtubules in the cells.

Besides impedance measurements, Image Correlation Spectroscopy (ICS) was applied to analyse pigment aggregation. The study shows for the first time that ICS can be used to analyse aggregation of non-fluorescent particles and suggests that the method may provide new information on the state of aggregation of granules in pigment cells.

Place, publisher, year, edition, pages
Linköping: Linköpings universitet, 2003. 58 p.
Series
Linköping University Medical Dissertations, ISSN 0345-0082 ; 803
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-26657 (URN)11222 (Local ID)91-7373-491-8 (ISBN)11222 (Archive number)11222 (OAI)
Public defence
2003-09-26, Victoriasalen, Hälsouniversitetet, Linköping, 09:00 (Swedish)
Opponent
Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2012-10-17Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMedFull-text

Authority records BETA

Immerstrand, CharlotteNilsson, HarrietLindroth, MargarethaSundqvist, TommyMagnusson, Karl-EricHolmgren-Peterson, Kajsa

Search in DiVA

By author/editor
Immerstrand, CharlotteNilsson, HarrietLindroth, MargarethaSundqvist, TommyMagnusson, Karl-EricHolmgren-Peterson, Kajsa
By organisation
Medical MicrobiologyFaculty of Health SciencesCell biology
In the same journal
Bioscience Reports
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 130 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf