Identification and characterization of Pkhd1, the mouse orthologue of the human ARPKD gene.
PKHD1, the gene mutated in human autosomal recessive polycystic kidney disease has recently been identified. Its translation products are predicted to belong to a superfamily of proteins involved in the regulation of cellular adhesion and repulsion. One notable aspect of the gene is its unusually complex pattern of splicing. This study shows that mouse Pkhd1 and its translation products have very similar properties to its human orthologue. Mouse Pkhd1 extends over approximately 500 kb of genomic DNA, includes a minimum of 68 nonoverlapping exons, and exhibits a complex pattern of splicing. The longest ORF encodes a protein of 4059aa predicted to have an N-terminal signal peptide, multiple IPTs and PbH1 repeats, a single transmembrane span (TM), and a short cytoplasmic C-terminus. Although the protein sequence is generally well conserved (approximately 73% average identity), the C-termini share only 55% identity. The pattern of Pkhd1 expression by in situ hybridization was also examined in developing and adult mouse tissues over a range of ages (E12.5 to 3 mo postnatal). High levels of expression were present in renal and biliary tubular structures at all time points examined. Prominent Pkhd1 signals were also found in a number of other organs and tissues. Tissue-specific differences in transcript expression were revealed through the use of single exon probes. These data show that key features of human PKHD1 are highly conserved in the mouse and suggest that the complicated pattern of splicing is likely to be functionally important.
Department of Medicine and Genetics, Johns Hopkins University, Baltimore, Maryland 21205, USA.
Yasuyuki
Y
Nagasawa
Sonja
S
Matthiesen
Luiz F
LF
Onuchic
Xiaoying
X
Hou
Carsten
C
Bergmann
Ernie
E
Esquivel
Jan
J
Senderek
Zhiyong
Z
Ren
Raoul
R
Zeltner
Laszlo
L
Furu
Ellis
E
Avner
Markus
M
Moser
Stefan
S
Somlo
Lisa
L
Guay-Woodford
Reinhard
R
Büttner
Klaus
K
Zerres
Gregory G
GG
Germino
D000818:Animals; D005091:Exons / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D023281:Genomics; D006801:Humans; D017403:In Situ Hybridization; D007684:Kidney Tubules / Q000196:embryology / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics*; D012326:RNA Splicing / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface / Q000235:genetics*; D050396:TRPP Cation Channels
D011506:Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D050396:TRPP Cation Channels; C451750:PKHD1 protein, human