ERK-activated CK-2 triggers blastema formation during appendage regeneration

Area of Science:

• Cellular Biology
• Developmental Biology
• Regenerative Medicine

Background:

• Appendage regeneration depends on blastema formation at injury sites.
• Early signaling pathways initiating blastema formation remain largely unknown.

Purpose of the Study:

• To identify novel signaling pathways that trigger blastema formation during appendage regeneration.
• To investigate the role of casein kinase 2 (CK-2) in cockroach leg regeneration.

Main Methods:

• Utilized RNA interference (RNAi) to knock down CK-2 expression in *Periplaneta americana*.
• Investigated CK-2 activation via ERK-induced phosphorylation post-amputation.
• Examined the conserved role of CK-2 in zebrafish caudal fin regeneration.

Main Results:

• Extracellular signal-regulated kinase (ERK) rapidly activates casein kinase 2 (CK-2) through phosphorylation in regenerating cockroach legs.
• CK-2 knockdown significantly inhibits blastema formation by suppressing cell proliferation and down-regulating mitosis genes.
• The regenerative function of CK-2 in promoting blastema cell proliferation is evolutionarily conserved in zebrafish.

Conclusions:

• ERK-activated CK-2 is a critical initiator of blastema formation in appendage regeneration.
• CK-2 plays a conserved role in promoting blastema cell proliferation across different species.
• This research elucidates key early signaling events in appendage regeneration initiation.