OTRS/Znuny 7 "To" field not filled after creating ticket via REST-API

Question

I'm using the OTRS REST API to create tickets in OTRS/Znuny 7. The ticket creation process is successful, but when I want to answer a ticket, it doesn't fill the "To" field.

My question is: Do I have to set a specific field, that the "To" field is filled with the given "From" E-Mail?

Request body

{
    "UserLogin":"root@localhost",
    "Password":"root",
    "Ticket":{
       "Queue":"Raw",
       "Title":"Test Ticket",
       "State":"new",
       "Priority":"3 normal",
       "CustomerUser":"customer-1"
    },
    "Article":{
        "CommunicationChannel": "Email",
        "From": "Znuny System <znuny@localhost>",
        "Subject": "Lorem ipsum",
        "Body": "Lorem ipsum dolor sit amet",
        "HistoryType": "EmailAgent",
        "ContentType": "text/plain; charset=utf-8"
    },
    "Attachment" :     
}