Does Coinbase send emails from subdomains?

I've noticed that some emails I've received from Coinbase seem to be coming from subdomains. Is this normal? Should I be concerned about the authenticity of these emails? I've heard about phishing scams targeting cryptocurrency users, so I want to make sure I'm not falling for one. Could you clarify if Coinbase does indeed send emails from subdomains, and if so, how can I verify the authenticity of these emails?