messages.content: 请把下面的中文句子翻译成英文
messages.role: system
messages.content: 迄今为止，人们对ORF4 所参与的细胞生物学过程知之甚少。
messages.role: user
messages.content: However, little is known about the interaction proteins of ORF4 which hindered better understanding the biological functions of ORF4 in the life cycle of PCV2.
messages.role: assistant