Widely watched CLSA bank analyst Mike Mayo said banks could take lessons from the major changes Morgan Stanley implemented post-financial crisis.

He made the comments on CNBC's "Fast Money," hours after Morgan Stanley wrapped up its annual meeting.

"Big brother banking is the environment that we're currently in. The government is more involved in the affairs of banks than ever before. And guess who got the memo early? Morgan Stanley," said Mayo. "I'm looking at where they've come from in the last five years. They revamped their business model. Wealth management used to be one third of the business. Now, it's one half."

Mayo has an "outperform" rating and a $40 price target on the bank. Shares are up 28 percent over the past year. The stock closed at $30.33 on Tuesday.

Since the 2007 peak, Morgan Stanley shares are down 56 percent.