cI gene

[ChuCDJK]

I am trying to find out some information on the cI gene in lamda phages,
which I believe somehow suppresses the lytic cycle, thereby inducing
lysogeny.  I was wondering if anyone could confirm this.  Furthermore, I
have two questions:

1) What does the cI gene encode, and how does this gene-product suppress
the lytic cycle?

2) Does the cI gene occur only the lamda genome, or does it also occur on
the genophores or plasmids of certain host strains?

Thank you very much, in advance

Sincerely, 

Chenghuan Chu