Molecular organization, expression and chromosomal localization of the mouse pronapsin gene

Abstract

Napsins have been identified only very recently as new aspartic proteinases of the pepsin family. Isolation, sequencing and functional analysis of the mouse genomic locus indicates that the organization of the pronapsin gene into nine exons is identical to that of other mammalian aspartic proteinase precursors, including pepsinogen. However, the additional C-terminal residues, which are a distinguishing feature of napsins, are encoded within exon 9 and not within an additional exon. Quantitation of pronapsin mRNA using RT-PCR indicates that the gene is transcribed in lung, kidney and spleen but not in heart. Regulation of gene expression was not influenced by the extent of CpG methylation but depended on the recognition of potential binding motifs in the promoter region by specific transcription factors such as YY-1. The single copy of the mouse pronapsin gene was located on chromosome 7. In humans, there are two pronapsin genes and, based on the mouse information, preliminary structures were deduced for these from sequences in the human genome databases. They appear to be located together on chromosome 19.

An aspartic proteinase gene family in the filamentous fungus Botrytis cinerea contains members with novel features

“…This proportion fluctuates with growth rates, resulting in different intensities of Bcact mRNA even when equal amounts of total RNA are loaded on a gel. Fluctuations in the levels of actin mRNA were reported previously in similar types of analyses in other organisms (Cook et al, 2001;Tatnell et al, 2000). Transcript levels of Bcap5 were generally low and seemed to largely follow the actin transcript levels, indicative of a constitutive but growth-dependent expression, with one exception.…”

Processing of Pulmonary Surfactant Protein B by Napsin and Cathepsin H

“…PCR primers were designed based on the published mouse napsin DNA sequence (17,27) and napsin amplified from type II cell cDNA. The napsin cDNA was subsequently cloned into pET21 (Novagen) and then transformed into Escherichia coli BL21(DE3) cells.…”

Regulation of human and mouse procathepsin E gene expression

“…RNA from human tissues was obtained from Clontech (Palo Alto, CA, USA). First‐strand cDNA was synthesized with M‐MLV reverse transcriptase using random hexamer primers as described previously [1]. The stability of RNA and cDNA samples prepared and stored at −70 °C was analysed by making repeat PCR measurements at appropriate intervals.…”

“…In mammals, individual aspartic proteinases are often found only in certain cells and tissues, e.g. pronapsin A in human lung and kidney [1], prorenin in the juxtaglomerular cells of the kidney and in human reproductive organs [2], and progastricsin which is present in human stomach and is also secreted from the acinar cells lining the prostate so that the mature enzyme, gastricsin, is found in high concentrations in seminal fluid [3,4]. In contrast, pepsinogen A is produced only within the chief cells lining the human stomach [5].…”