Expression characteristics and functional analysis of Krüppel-like factor 4 in adductor muscle and mantle of Zhikong scallop Chlamys farreri

Abstract

Krüppel-like factor 4 (KLF4) is an important transcription factor involving in formation and maintenance of muscles in mammals. However, no data are available on KLF4 function in shellfish muscles which play vital roles in the movement, stress response, and physiology in shellfish. In the present study, we revealed that the Klf4 mRNA of Zhikong scallop Chlamys farreri was expressed in most tissues, which has high level in adductor muscle, mantle, kidney, and testis. Positive signals of the Klf4 mRNA and protein were visible in all skeletal muscle fibers of adductor muscle, and all the cells of C. farreri mantle. Furthermore, the knockdown of Klf4 mRNA in adductor muscle and mantle by means of in vivo RNA interference led to some different phenotypes, including disordered arrangement of muscle fibers in adductor muscle and mantle, abnormal structures of skeletal muscles, and reduced muscle fibers under endepidermis of mantle. Our findings demonstrated that Klf4 plays important roles in maintenance of muscle functions in C. farreri adductor muscle and mantle, and suggested that its regulatory way in skeletal muscle may be different from the smooth muscle in shellfish.

Effects of Benzo[a]pyrene on Food Metabolism and Reproductive Endocrine and Ovarian Development in Female Scallop Chlamys farreri at Different Reproductive Stages

“…Both Wnt and β-catenin were downregulated at the proliferation and growth stages, and therefore we propose that B[a]P inhibited the oogenesis of C. farreri. Yang et al (2019) found that in C. farreri the Myc mRNA level increased gradually in the ovary along with gonadal development, and that a Myc-positive signal was located in oocytes at each stage; however, how Myc regulates gonad development and gametogenesis in the ovary remains unknown. The expression of Myc was significantly induced in the growth and mature stages of the ovary following B[a]P treatment, which promoted the proliferation of ovarian cells, but the mechanism needs to be further studied.…”

“…We used β-actin as the reference gene because of its stable expression in previous experiments (Yang et al, 2020a). The primer for myelocytomatosis viral oncogene (Myc) was based on the research of Yang et al (2019). The genes we measured were obtained from the transcriptome of C. farreri, and the National Center for Biotechnology Information accession numbers are SPR238487 (gonads), SRP268573 (gonads), and SRP311574 (digestive glands).…”