Four isoforms of the signal-transduction and RNA-binding protein QKI expressed during chicken spermatogenesis

Abstract

Genes expressed during spermatogenesis undergo alternative initiation and alternative splicing and may be under the control of a coordinated mechanism of RNA processing. A family of proteins that combine features of signal‐transduction and RNA‐binding molecules could be instrumental in this process. We have characterized a cDNA from adult chicken testis that codifies a highly conserved member of the STAR protein family, the orthologue of the mouse quakinggene qkI. The predicted chicken protein differs only in four amino acids from the corresponding mouse protein. Messages of 7, 6, and 5 kb are expressed differentially during chicken spermatogenesis. The 5‐kb message, the predominant form in adult testis, presents heterogeneity in the coding region, showing insertions of 51 and 75 bp and a deletion of 24 bp, which gives rise to four possible isoforms of the protein. Mol. Reprod. Dev. 50:70–78, 1998. © 1998 Wiley‐Liss, Inc.

Apoptosis of porcine Sertoli cells is inhibited by QKI-5 via regulating CASP8

“…QKI can express four subtypes during the development of chicken sperm (Mezquita et al 1998), and quaking (qkv mutant) mice also show severe https://doi.org/10.17221/158/2018-CJAS sperm maturation disorders. In addition, the study showed that QKI expression is increasing in 1-to 7-month-old boar's testes (Zhang et al 2015).…”

Expression of lactate dehydrogenases A and B during chicken spermatogenesis: Characterization of testis specific transcripts

“…As shown in Figure 6, treatment with Actinomycin D did not affect markedly the level of LDH-B mRNA. Most of the LDH-B mRNA (85%) and only a 45% of LDH-A remained after 9 h of treatment with Actinomycin D. In contrast, the level of the 6kb quaking transcript QKI, coding for a signal transduction and RNA-binding protein expressed during spermatogenesis [Mezquita et al, 1998a], dropped more rapidly (90% in 9 h). The stability of chicken testis LDH-A mRNA is higher that the previously reported in C6 glioma cells [Jungmann et al, 1983] and similar to the stability measured in Sertoli cells [Boussouar and Benahmed, 1999].…”

Comparative Nucleotide Sequence of Encoding for Quaking Protein of Birds and Mammals~!2008-09-26~!2008-11-07~!2008-12-05~!

“…The sequence of our chicken qkI and that of Mezquita's chicken qkI [2] are the same, but the source organs are different. This shows that the three bases defect and the twenty four base alternative splicing in exon 6 of qk are normal and ubiquitous in the chicken.…”

“…The mouse quaking I (qkI) gene, encoding a KH domain containing RNA-binding protein [1], was first isolated as a candidate gene for neurological mutation, quaking viable, and was known as a model for human leukodystrophy [2]. Genes highly homologous to qkI have been found in various animal species from nematodes to humans [3][4][5][6][7], and mutations in these genes result in various developmental defects other than demyelination.…”