Arheje i evolucija eukariota

undergraduate thesis

• Title (english): Archaea and the evolution of eukaryotes
• Author: Mario Đura
• Mentor: Damjan Franjević (mentor)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2021-08-31, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Samo posljednja 4 desetljeća, arheje su prepoznate kao zasebna domena života, prije čega su bile svrstavane pod domenu bakterija. Inicijalna saznanja su se oslanjala isključivo na uzgojive ekstremofilne predstavnike arheja, sve do razvoja sofisticiranijih molekularnih metoda pretraživanja genoma u okolišu. Njima se ispostavilo da arheje obitavaju u gotovo svim okolišima i to u znatnoj zastupljenosti. Recentnijih desetljeća se ponajviše proširilo znanje o njihovoj genetskoj raznolikosti i sličnostima s eukariotskom domenom. Monofilija svih grupa još uvijek je predmet istraživanja te veoma često se pronalaze dublja grananja grupa ili novi razredi. Fiziološki, arheje sadrže karakteristike nalik bakterijama, karakteristike nalik eukariotima te potpuno individualne značajke. Štoviše, sličnije su eukariotima nego bakterijama na molekularnoj razini. Otkriće Asgard supergrupe arheja približava nas spoznaji događaja tijekom postanka i ranog razvoja eukariota. Sukladno tome, ustanovljeno je da su eukarioti ogranak arhealne domene, kao potomci Asgard arheja i bakterijskih endosimbiota. Potpuni opseg eukariotskih značajci koje možemo pripisati arhealnom pretku predmet su mnogih teorija. Njih će jedino razlučiti daljnje proširenje filogenetske raznolikosti te buduće kultivacije arheja.

Abstract (english)

Only for the past 4 decades, archaea have been recognised as a separate domain of life, being classified as bacteria beforehand. Our initial findings have exclusively relied upon cultivatable extremophilic representatives of archaea, up until the development of more sophisticated molecular methods for surveying environmental genomes. Their use made apparent that archaea appear in all environments and in substantial quantities. In the recent decades we have most expanded our knowledge about their genetic diversity and their similarities with the domain of eukaryotes. The monophyly of all groups if still a subject of research and, very often, deeper branchings or new phyla are being found. Physiologically, archaea possess bacterial-like characteristics, eukaryote-like characteristics and distinctly archaeal properties. Furthermore, they are more alike eukaryotes than bacteria on the molecular scale. The discovery of the Asgard superphylum has brought us closer to understanding events that happened during eukaryogenesis. Following that notion, it has been established that eukaryotes are a branch of the archaeal domain, as descendants of Asgard archaea and bacterial endosymbionts. The full extent of eukaryotic properties which we ascribe to an archaeal ancestor is a subject of many theories. They will only be resolved by further expansion of phylogenetic diversity and future archaeal culturing.

• Keywords: arheje; raznolikost; ekologija; filogenija; Asgard; evolucija; eukariogeneza; LECA
• Keywords (english): archaea; diversity; ecology; phylogeny; Asgard; evolution; eukaryogenesis; LECA
• Language: croatian
• URN:NBN: urn:nbn:hr:217:466012
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) molekularne biologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-09-23 11:39:26