The Drosophila Polycomb group gene Sex comb on midleg (Scm) encodes a zinc finger protein with similarity to polyhomeotic protein

The Sex comb on midleg (Scm) gene is a member of the Polycomb group (PcG) of genes in Drosophila melanogaster. The PcG genes encode transcriptional repressors required for proper spatial expression of homeotic genes. We report the isolation of new Scm mutations and the molecular characterization of the Scm gene. Scm mRNA is expressed maternally, at peak levels in early embryos and then at lower levels throughout the remainder of development. Scm encodes a putative zinc finger protein of 877 amino acids. Scm protein is similar to polyhomeotic, another member of the PcG, both in the zinc finger region and in a separate C-terminal domain of 60 amino acids, which we term the SPM domain. Sequence analysis of an Scm mutant allele suggests a functional requirement for the SPM domain. Scm protein also bears homology in multiple domains to a mouse protein, Rae-28 (Nomura, M., Takihara, Y. and Shimada, K. (1994) Differentiation 57,39-50) and to a fly tumor suppressor protein, the product of the lethal(3)malignant brain tumor gene (Wismar, J. et al., (1995) Mech. Dev. 53, 141–154). Possible functional relationships among these proteins and potential biochemical roles for Scm protein in PcG repression are discussed.

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ZAP, a CCCH-Type Zinc Finger Protein, Inhibits Porcine Reproductive and Respiratory Syndrome Virus Replication and Interacts with Viral Nsp9

Journal of Virology ◽

10.1128/jvi.00001-19 ◽

2019 ◽

Vol 93 (10) ◽

Cited By ~ 4

Author(s):

Yongxiang Zhao ◽

Zhongbao Song ◽

Juan Bai ◽

Xuewei Liu ◽

Hans Nauwynck ◽

...

Keyword(s):

Amino Acids ◽

Zinc Finger ◽

Transcriptome Sequencing ◽

Zinc Finger Protein ◽

Early Stage ◽

Respiratory Syndrome Virus ◽

Type I ◽

Zinc Finger Domain ◽

Antiviral Protein ◽

Finger Protein

ABSTRACTPorcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important pathogens affecting many swine-producing regions. Current vaccination strategies and antiviral drugs provide only limited protection. PRRSV infection can cleave mitochondrial antiviral signaling protein (MAVS) and inhibit the induction of type I interferon. The antiviral effector molecules that are involved in host protective responses to PRRSV infection are not fully understood. Here, by using transcriptome sequencing, we found that a zinc finger antiviral protein, ZAP, is upregulated in MAVS-transfected Marc-145 cells and that ZAP suppresses PRRSV infection at the early stage of replication. We also found that the viral protein Nsp9, an RNA-dependent RNA polymerase (RdRp), interacts with ZAP. The interacting locations were mapped to the zinc finger domain of ZAP and N-terminal amino acids 150 to 160 of Nsp9. These findings suggest that ZAP is an effective antiviral factor for suppressing PRRSV infection, and they shed light on virus-host interaction.IMPORTANCEPRRSV continues to adversely impact the global swine industry. It is important to understand the various antiviral factors against PRRSV infection. Here, a zinc finger protein, termed ZAP, was screened from MAVS-induced antiviral genes by transcriptome sequencing, and it was found to remarkably suppress PRRSV replication and interact with PRRSV Nsp9. The zinc finger domain of ZAP and amino acids 150 to 160 of Nsp9 are responsible for the interaction. These findings expand the antiviral spectrum of ZAP and provide a better understanding of ZAP antiviral mechanisms, as well as virus-host interactions.

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