On the one hand, this type of organizational structure benefits from having individuals entirely dedicated to one function. In some cases, there can be cost savings and efficiency gains in combining functions in this way. However, this type of organizational structure is prone to conflict.
The alpha subunit (RpoA) initiates RNAP assembly by dimerising to form a platform on which the beta subunits can interact. The alpha subunit consists of a N-terminal domain (NTD) and a C-terminal domain (CTD), connected by a short linker.
Similarities: Comparisons between bacterial and RNA polymerase II have been performed. Similarity in sequence has been shown between alpha, Rpb3, and Rpb11. Alpha 2 binds beta to form a subcomplex that then binds betaâ that form the core enzyme. Rpb3 and Rpb11 also form a subcomplex with Rpb2. The Rpb3 and Rpb11 show the same fold as the alpha subunit in bacterial polymerase. Beta and Rpb2 as well as betaâ and Rpb1 show sequence homology. The pore in which RNA exits and where NTPs comes into the polymerase are conserved as well (4).