Avtor/Urednik		Starčič-Erjavec, Marjanca; Jordi, Bart JAM; Gaastra, Wim; van Putten, Jos; Žgur-Bertok, Darja
Naslov		CRP, H-NS in Lrp so pozitivni regulatorji promotorja PtraJ operona tra plazmida pRK100 bakterije Escherichia coli
Tip		članek
Vir		In: Klanjšek M, editor. Raziskovalno delo podiplomskih študentov v Sloveniji. Ljubljana: Društvo mladih raziskovalcev,
Leto izdaje		2003
Obseg		str. 405-14
Jezik		slo
Abstrakt		CRP, H-NS and Lrp are Positive Regulators of tra Operon PtraJ Promoter of the Escherichia coli Plasmid pRK100 - Conjugative transfer of F-like plasmids is a tightly regulated process. The TraJ protein is the main positive regulator of the genes involved in this process. Little is known about the regulation of the expression of traJ itself. We used a traJ-lacZ transcriptional fusion to study the effect of global regulators on the expression of traJ. CRP, H-NS and Lrp were shown to have a positive effect on the expression of traJ from the pRK100 plasmid. Competitive RT-PCR showed that all three proteins exert their effect at the level of transcription. Binding of CRP, H-NS and Lrp to the traJ promoter was demonstrated by mobility shift assays and was shown to be the most specific for the CRP protein. The positive effect of these regulators was confirmed by in vivo conjugative transfer experiments.
Izvleček		Konjugacijski prenos F plazmidu podobnih plazmidov je proces, ki je močno uravnan. Protein TraJ je glavni pozitivni regulator genov, ki so vpleteni v konjugacijski prenos. Znano je, da sistem FinOP preprečuje nastanek proteins TraJ, o uravnavanju izražanja samega gena traJ pa je le malo znanega. Da bi preučili učinek globalnih regulatorjev bakterije Escherichia coli (E. coli) na aktivnost promotorja PtraJ smo uporabili gensko transkripcijsko fuzijo traJ-lacZ. V teh poskusih smo odkrili, da imajo globalni regulatorji CRP, H-NS in Lrp pozitivni učinek na izražanje traJ plazmida pRK100. Kompetitiven RT-PCR je razkril, da vsi trije globalni regulatorji delujejo na ravni transkripcije in testi mobilnosti so pokazali, da se vsi trije proteini, CRP, H-NS in Lrp, vežejo na promotor PtraJ. Testi mobilnosti so nadalje pokazali, da je vezava CRP specifična, medtem ko sta vezavi Lrp in H-NS manj specifični. CRP, H-NS in Lrp so pozitivno delovali tudi v in vivo poskusu konjugacijskega prenosa, kar nakazuje, da so ti trije globalni regulatorji pomembni za konjugacijski prenos.
Deskriptorji		PLASMIDS ESCHERICHIA COLI F FACTOR CONJUGATION, GENETIC GENE FREQUENCY POLYMERASE CHAIN REACTION TRANSCRIPTION, GENETIC