Enough with the letters, Gov. Mark Dayton told Republican lawmakers Thursday.

Irked by a letter calling on his chief of staff to resign over an appointment Dayton made five months ago, the governor took aim at his inbox.

"This has become a pattern with Republican legislators, who are either bored or craving attention," Dayton told reporters who received a copy of the letter Wednesday. "So they send a letter that the press gets at the same time, or often before, I do. So that tells you right away what the intent of the letter is."

Dayton receives regular missives from GOP lawmakers on issues ranging from problems with the MNsure health insurance exchange to concerns about the secretary of state's online voter registation efforts.

"It's not about constructively working on something that someone has a concern about," Dayton said "It's about getting press attention. And as long as they keep getting press attention, I expect those letters will continue to be forthcoming."

The latest letter was delivered by state Rep. Peggy Scott, R-Andover, who raised concerns about possible conflicts of interest arising from Dayton's appointment of his chief of staff to head Mayo Clinic's Destination Medical Center Corporation board. Dayton named Tina Smith to the Mayo board in July and she was unanimously voted in as chair by the rest of the board.

Scott wrote Dayton Tuesday, asking for Smith's resignation, saying her dual roles create "an ethical conflict for the governor's office or the DMCC."

Smith, who worked to persuade the Legislature to sign off on half a billion dollars in state taxpayer support for the Destination Medical Center project in Rochester, was named to the board position by the governor and unanimously approved by the other members of the board.

Dayton spokesman Bob Hume noted that the governor's general counsel reviewed the relevant statues and requirements before Smith's appointment and concluded that there was no legal impediment. The legislative auditor, in response to another letter from Scott, also said Smith's appointment was legal.

"I've never heard anybody question Tina Smith's loyalty of duty to any of her responsibilities," Dayton said. "For anyone to impugn her integrity, the ethics of her taking that position, is just totally ludicrous and just an attempt to get some attention."

House Minority Leader Kurt Daudt fired back.

"Representative Scott is a hardworking legislator who is asking appropriate and tough questions of the Dayton administration," Daudt said in a statement. "Minnesota taxpayers deserve answers to these important questions not dismissive and patronizing responses from the chief executive."

Daudt noted that Scott has not yet received a letter from Dayton in response to her letter.