Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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
Gene Expression Analysis of Loto-Type Toll Receptors in the Onychophoran Euperipatoides kanangrensis
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
2017 (English)Independent thesis Advanced level (degree of Master (Two Years)), 180 HE creditsStudent thesisAlternative title
Analys av genuttrycket hos Loto-typ receptorer i klomasken, Euperipatoides kanangrensis (Swedish)
Abstract [en]

The expression and role of Loto genes was previously investigated in arthropods and it was concluded that the morphogenetic functions of Loto genes were conserved in the last common ancestors of arthropods. In this paper, possible orthologs of Loto clade genes are analysed and it was found that they possibly play a conserved role in convergent extension of cells from the blastoderm stage to germ band extension stage. The differences and similarities in the number of and expression of Loto clade genes in arthropods and onychophorans are compared and analysed. Unlike in arthropods, the expression of Euperipatoides Loto is strongest in the head including part of the somewhat enigmatic frontal appendages (the onychophoran antennae). I also find a stripped segmental pattern of expression that is similar to that classic expression in transverse segmental stripes of Loto class genes as seen in arthropods. However, these stripes are only week and appear to be mesodermal rather than ectodermal, as in arthropods. These facts are discussed in regard to current hypothesis about the origin of segmentation in panarthropods.Insects, crustaceans and chelicerates each possess a set of several Loto class genes which are also involved in convergent extension. But the myriapod Strigamia only appears to possess one such gene.  I therefore investigated Loto genes in another distantly related myriapod, Glomeris. It appears to only have one Loto gene and this appears to be involved in convergent extension as well. Two Toll genes  of Glomeris (Gm-567 and Gm-596) were incomplete and could according to phylogenetic analysis represent Loto genes. I therefore checked their expression and found that they are not expressed like Loto genes. A third potential Glomeris Loto gene (Gm-399) could not be isolated via PCR.My data suggest a somewhat different role for onychophoran Loto than convergent extension, and that the ancestral set of panarthropod Loto genes may be one, rather than a set.

Abstract [sv]

Loto-genernas roll och uttryck var tidigare undersökt inom leddjur och slutsatsen var att morfogenetiska funktioner av Loto-gener var konserverade hos närmsta förfäderna till leddjuren. I denna artikel/rapport studerades ortologer till Loto-generna, vilket kunde konstateras att dessa förmodligen har en viktig roll i konvergent förlängning (convergent extension) av celler från blastoderma stadiet till germ band stadiet. Skillnader och likheter i uttryck av Loto-gener inom leddjur och Onychophora (klomaskar) jämfördes och analyserades. Olikt från leddjur så var uttrycket av Euperipatoides Loto som starkast i antennen vid huvudet på Onychophora. Jag kunde också se ett segmenterat mönster av uttrycket som är liknande de uttryck i form av segmentell band som återfinns i klassen Loto-gener hos leddjuren. Dessa är dock svaga och verkar bara vara mesodermala snarare än ektodermala som hos leddjur. Dessa fakta diskuteras kring hypotesen kring ursprunget om segmentering hos Panarthropoda.Insekter, kräftdjur och palpkäkar har alla flera klasser av Loto gener som även de är inblandade konvergent förlängning. Men, myriapod Strigamia har bara en Loto-gen. Därför valde jag att utforska de Loto-gener i en annan långt relaterad myriapod kallad Glomeris. Det verkar som Glomeris har en Loto-gen och den är involverad i konvergent förlängning också. Två Toll-gener från Glomeris (Gm-567 och Gm-596) var inte kompletta och kunde representera Loto-gener enlig analys från phylogenetiskt träd. Därför kollade jag uttrycket på dessa gener och kunde se att de inte var uttryckta i samma grad som Loto-gener. En tredje potentiell Glomeris Loto-gen (Gm-399) kunde inte bli isolerad med hjälp av PCR.Min data tyder på att klomaskars Loto-gener har en annan roll än konvergent förlängning och attpanarthropods kanske bara hade en Loto-gene istället för ett set av gener.

Place, publisher, year, edition, pages
2017. , p. 26
Series
Examensarbete vid Institutionen för geovetenskaper, ISSN 1650-6553 ; 417
Keyword [en]
Panarthropods, Loto genes, Convergent extension
National Category
Evolutionary Biology
Identifiers
URN: urn:nbn:se:uu:diva-334158OAI: oai:DiVA.org:uu-334158DiVA, id: diva2:1158873
Educational program
Master Programme in Earth Science
Presentation
2017-09-18, Norrland 1, Geocentrum, Villavägen 16, Uppsala, 14:00 (English)
Supervisors
Examiners
Available from: 2017-11-21 Created: 2017-11-21 Last updated: 2017-11-21Bibliographically approved

Open Access in DiVA

fulltext(1447 kB)34 downloads
File information
File name FULLTEXT01.pdfFile size 1447 kBChecksum SHA-512
04b94fef817e15fe8c114dd7d83a2cd04ddc793b5146b1df3631a94a784a1cb867e3a4714470b59e0aadf569de187bd89828d0792f540560fb1329b04cb801fe
Type fulltextMimetype application/pdf

By organisation
Department of Earth Sciences
Evolutionary Biology

Search outside of DiVA

GoogleGoogle Scholar
Total: 34 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 60 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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