Can POCO / Domain objects have dependencies injected to it

This is my current code structure for the business layer -

• UserManager (service class) works on User (domain object)
• CompanyManager (service class) works on Company (domain object)

Now, both my domain objects depend on

• IUnitOfWork - (uses IUserRepository, ICompanyRepository)

I have read articles where it says domain objects should not have any dependencies on repositories. So my question is in two parts -

1. Whether domain objects shouldn't have any dependencies? In the above case, what if some operation on 'Company' should trigger some operation on 'User', then can the Company object have a dependency on UserManager?
2. If the domain object shouldn't have dependencies, then where should I keep those logic? Where should I call the save method on repository, or a call to UserManager when something happens on 'Company'?

Thanks!