| Sažetak | Mehanizmi evolucije genoma zanimljiva su tematika kojom se unutar biologije bavi molekularna
evolucija, a osobito je među mehanizmima evolucije zanimljiv fenomen poliploidije, neobičnog
adaptacijskog mehanizma koji se očituje u preživljavanju stanica s povećanim brojem kromosoma
nego što je to slučaj kod predačke vrste/populacije. Poliploidija je poznata kod mnogih eukariota i
prokariota, a može biti obilježje svih stanica ili samo određenih tkiva. Od pojave kod ranjenog
tkiva i onoga koje je pod značajnim stresom, metabolički aktivnih tkiva i gigantskih udova do
modifikacije pripadnika eusocijalnih zajednica; poliploidija ima značajnu ulogu u razvoju,
adaptaciji i specijaciji organizama. Filogenetički gledano, mnogo je češća kod biljaka nego kod
životinja, a jednako je tako i kod biljaka mnogo bolje istražena nego kod životinja. Primjeri utjecaja
poliploidije na brzu specijaciju i regulaciju ploidnosti potomstva kod kukaca temeljna su hipoteza
ovog istraživanja. U ovom radu za cilj imam umjetno inducirati tetraploidiju u matice medonosne
pčele (Apis mellifera Linnaeus, 1758) koja bi možda mogla partenogenetski stvarati radilice, a
oplodnjom triploide. Osim teoretskog istraživanja proveo sam nekoliko pokusa na ličinkama i
jajima medonosne pčele, mrava i paličnjaka, gdje sam stanice tretirao citostatikom kolhicinom.
Svo potomstvo pčela, tretirano ili ne, je bilo ubijeno od strane radilica. Rad s pčelama je bio
tehnički iznimno zahtjevan te za dobivanje rezultata potrebna je upotreba metoda uzgoja bez
prisutnosti radilica. Tretirano potomstvo mrava i paličnjaka je dalo žive jedinke koji ne pokazuju
morfološke razlike od kontrola. Iz provedenog istraživanja možemo zaključiti da indukcija
poliploidije u medonosnih pčela nije moguća izvan laboratorijskih uvjeta zbog tehničkih prepreka. |
| Sažetak (engleski) | Mechanisms of genome evolution are an interesting subject that is dealt with within biology by
molecular evolution, especially interesting mechanisms of evolution is the phenomenon of
polyploidy, an unusual adaptation mechanism that manifests itself in the survival of cells with an
increased number of chromosomes compared to the case in the ancestral species/population.
Polyploidy is known in many eukaryotes and prokaryotes, and it can be a feature of all cells or
only certain tissues. From the appearance in wounded tissue and that which is under significant
stress, to metabolically active tissues and gigantic limbs, and through the modification of
members of eusocial communities; polyploidy plays a significant role in the development,
adaptation and speciation of organisms. Phylogenetically, it is much more common in plants than
in animals, and it is also much better studied in plants than in animals. Examples of the influence
of polyploidy on rapid speciation and regulation of offspring ploidy in insects are the basic
hypothesis of this research. In this work, I aim to artificially induce tetraploidy in queens of the
honey bee (Apis mellifera Linnaeus, 1758), which might be able to parthenogenetically create
workers, and triploids by fertilization. In addition to theoretical research, I conducted several
experiments on the larvae and eggs of honey bees, ants and phasmids, where I treated the cells
with the cytostatic colchicine. All bee offspring, treated or not, were killed by the workers.
Working with bees was technically extremely demanding, and in order to obtain results, it was
necessary to use breeding methods without the presence of workers. Treated progeny of ants and
phasmids produced live individuals that did not show morphological differences from controls.
From the conducted research, we can conclude that the induction of polyploidy in honey bees is
not possible outside of laboratory conditions due to technical obstacles. |
