Identify the topics and subject that you know well enough so that when you write (share updates), the community trusts that you know the subject. Building 'trust' is the first step towards engagement, and it is as true for individuals as it is for organizations.

Once you share an update, add your own perspective for the right CTA. Why should anyone engage with the post - are you giving them some food for thought? Are you questioning some industry recommended practice? Are you seeking opinion?

When you combine (a) your expertise that builds trust (b) Right CTA, people will be encouraged to contribute.

Important: Tag the sources as required. It adds authenticity to what you post. And then be timely and courteous while responding via comments.