MBIO 3430 Lecture Notes - Lecture 11: Transitional Fossil, Coevolution, Symbiosis
19 Oct 2018
School
Department
Course
Professor
Document Summary
All viruses do not: make their own proteins (host provides translation platform, produce energy via atp (host provides, reproduce by dividing (are assembled) Need host cell to provide these fu(cid:374)(cid:272)tio(cid:374)s a(cid:374)d p(cid:396)odu(cid:272)ts of (cid:862)pa(cid:396)ts(cid:863) fo(cid:396) vi(cid:396)us asse(cid:373)(cid:271)l(cid:455) Regressive hypothesis: endoparasites reduced to a minimal state that allows for host assisted replication/assembly and infection: pre existing symbiont reduced so much it needed host replication. Cellular origin hypothesis: escaped genetic elements gaining additional elements to (cid:862)(cid:396)epli(cid:272)ate(cid:863) (cid:894)host asse(cid:373)(cid:271)l(cid:455) (cid:396)e(cid:395)ui(cid:396)ed(cid:895) a(cid:374)d i(cid:374)fe(cid:272)t: mobile elements/units that could associate with other genes allowing it to be packaged and moved. Coevolution hypothesis (virus first): virus evolved from selfish rna and dna molecules co-evolved with host cell. Or all three together: a heterogeneous assemblages of infectious agents that evolved independently of each other by a variety of mechanisms. Luca evolved from primordial gene pool housed within a network of inorganic compartments. Found within this gene pool were selfish rna and dna elements that evolved into viruses.
