Moody's downgrade of 10 mid-sized U.S. banks has led to a decline in their shares during Tuesday's premarket trading. The rating agency highlighted concerns over rising funding costs, possible declines in deposit levels, and weaker profitability, which pose risks to the banking sector. This comes after the industry faced a crisis earlier in the year due to the collapse of three lenders. The announcement by Moody's has been seen as a wake-up call by investors. It has raised concerns about its potential impact on U.S. growth, as regional banks are essential for financing small and mid-size enterprises.