Juvenile hormone-independent function of Krüppel homolog 1 in early development of water flea Daphnia pulex

Hitoshi Miyakawa, Minae Watanabe, Marina Araki, Yukiko Ogino, Shinichi Miyagawa, Taisen Iguchi

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Elaborate regulation of insect metamorphosis is the consequence of physiological cooperation among multiple endocrine factors such as juvenile hormones (JHs) and ecdysteroids. Hormone-induced transcription factors play important roles in substantive interactions between hormonal signaling pathways. In insects, zinc finger transcription factor Krüppel homolog 1 (Kr-h1) is a key gene of the endocrine signaling pathway in which it is directly upregulated by JH receptor Methoprene-tolerant (Met) in the presence of JH and then regulates multiple downstream factors, including components of the ecdysteroid signaling pathway. Although JH also plays a role in various biological phenomena in other arthropod species, little is known about the molecular basis of the JH signaling pathway. Here we cloned Kr-h1 from a branchiopod crustacean, Daphnia pulex, (DappuKr-h1) and analyzed its expression profile and developmental function together with consideration of its relationship to the JH signaling pathway. We suggest that DappuKr-h1 lacks JH responsiveness and regulatory relationship with the JH receptor. Moreover our loss-of-function analysis revealed that maternal mRNA of DappuKr-h1 plays a critical role in early development independent from the JH signaling pathway. These findings provide insights about whether and how the JH signaling pathway influenced evolution, leading to greater diversity in phylum Arthropoda.

Original languageEnglish
Pages (from-to)12-18
Number of pages7
JournalInsect Biochemistry and Molecular Biology
Volume93
DOIs
Publication statusPublished - Feb 2018

Keywords

  • Daphnia pulex
  • Juvenile hormone
  • Krüppel homolog 1
  • Regulatory divergence

Cite this