An ANKRD11 exonic deletion accompanied by a congenital megacolon in an infant with KBG syndrome

KBG syndrome is an autosomal dominant syndrome presenting with macrodontia, distinctive facial features, skeletal anomalies, and neurological problems caused by mutations in the ankyrin repeat domain 11 (ANKRD11) gene. The diagnosis of KBG is difficult in very young infants as the characteristic macrodontia and typical facial features are not obvious. The youngest patient diagnosed to date was almost one year of age. We here describe a 2-month-old Korean boy with distinctive craniofacial features but without any evidence of macrodontia due to his very early age. He also had a congenital megacolon without ganglion cells in the rectum. A de novo deletion of exons 5–9 of the ANKRD11 gene was identified in this patient by exome sequencing and real-time genomic polymerase chain reaction. As ANKRD11 is involved in the development of myenteric plexus, a bowel movement disorder including a congenital megacolon is not surprising in a patient with KBG syndrome and has possibly been overlooked in past cases.

Crystal structure of the N-terminal ankyrin repeat domain of TRPV3 reveals unique conformation of finger 3 loop critical for channel function

In all six members of TRPV channel subfamily, there is an ankyrin repeat domain (ARD) in their intracellular N-termini. Ankyrin (ANK) repeat, a common motif with typically 33 residues in each repeat, is primarily involved in protein-protein interactions. Despite the sequence similarity among the ARDs of TRPV channels, the structure of TRPV3-ARD, however, remains unknown. Here, we report the crystal structure of TRPV3-ARD solved at 1.95 Å resolution, which reveals six-ankyrin repeats. While overall structure of TRPV3-ARD is similar to ARDs from other members of TRPV subfamily; it, however, features a noticeable finger 3 loop that bends over and is stabilized by a network of hydrogen bonds and hydrophobic packing, instead of being flexible as seen in known TRPV-ARD structures. Electrophysiological recordings demonstrated that mutating key residues R225, R226, Q255, and F249 of finger 3 loop altered the channel activities and pharmacology. Taken all together, our findings show that TRPV3-ARD with characteristic finger 3 loop likely plays an important role in channel function and pharmacology.

Heteromerization of TRP channel subunits: extending functional diversity

Transient receptor potential (TRP) channels are widely found throughout the animal kingdom. By serving as cellular sensors for a wide spectrum of physical and chemical stimuli, they play crucial physiological roles ranging from sensory transduction to cell cycle modulation. TRP channels are tetrameric protein complexes. While most TRP subunits can form functional homomeric channels, heteromerization of TRP channel subunits of either the same subfamily or different subfamilies has been widely observed. Heteromeric TRP channels exhibit many novel properties compared to their homomeric counterparts, indicating that co-assembly of TRP channel subunits has an important contribution to the diversity of TRP channel functions.

Molecular cloning and characterization of a gene encoding RING zinc finger ankyrin protein from drought-tolerant Artemisia desertorum.

A RING zinc finger ankyrin protein gene,designated AdZFP1, was isolated from drought-tolerant Artemisia desertorum Spreng by mRNA differential display and RACE.Its cDNA was 1723 bp and encoded a putative protein of 445 amino acids with a predicted molecular mass of 47.9 kDa and an isoelectric point (pI) of 7.49. A typical C3HC4- type RING finger domain was found at the C-terminal region of the AdZFP1 protein,and several groups of ankyrin repeats were found at the N-terminal region. Alignments of amino acid sequence showed that AdZFP1 was 66% identical to the Arabidopsis thaliana putative RING zinc finger ankyrin protein AAN31869.Transcriptional analysis showed that AdZFP1 was inducible under drought stress in root,stem and leaf of the plant.Semi-quantitative reverse- transcriptase-polymerase chain reaction (RT-PCR) analysis showed that the transcript of AdZFP1 was strongly induced by exogenous abscisic acid (ABA) and also by salinity,cold and heat to some extent.Overexpression of the AdZFP1 gene in transgenic tobacco enhanced their tolerance to drought stress.

Therapeutic Potential of Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Ischemic Myocardium

BACKGROUND AND OBJECTIVES: We designed this study to determine the therapeutic potentials of umbilical cord blood (UCB)-mesenchymal stem cells (MSCs), as compared with bone marrow (BM)-MSCs. MATERIALS AND METHODS: MSCs were isolated from UCB and BM. For the in vivo study, myocardial infarction was induced by ligation of the left anterior descending coronary artery (LAD) in rats for 30 min, and this was followed by release; the MSCs were then injected into a designated point around the infarcted area. Echocardiographs were performed two weeks after surgery. For the in vitro study, a cDNA microarray and cytokine array were performed to compare the MSCs from UCB and from BM. Cell migration was assessed by a wound scratch assay, and the level of cardiac ankyrin repeat protein (CARP) was determined by reverse transcriptase-polymer chain reaction (RT-PCR) or Western blot analysis. RESULTS: For the echocardiograph findings, the fractional shortening (FS) was 43.9% in the UCB-MSCs group and it was 38.6% in the BM-MSC group. The ejection fraction (EF) was 79.8% in the UCB-MSC group and it was 72.4% in the BM-MSC group (control FS: 26.2% and the control EF: 56.6%). CARP was one of the highly expressed genes in the UCB-MSCs on the cDNA microarray. The mRNA and the expressed level of CARP protein in the UCB-MSCs were higher than those in the BM-MSCs. The cell migration of the CARP small interfering ribonucleic acid (siRNA) transfected UCB-MSCs was delayed compared to that of the normal UCB-MSCs (p<0.05) CONCLUSION: Our study directly compared the two types of MSCs from UCB and BM, and we suggest that the CARP molecule might be responsible for the motility of UCB-MSCs.

The Expression of Cardiac Ankyrin Repeat Protein in an Animal Model of Adriamycin-Induced Cardiomyopathy

BACKGROUND AND OBJECTIVES: Cardiac ankyrin repeat protein (CARP) is an embryonic nuclear protein, and its expression is increased under conditions of pressure or volume overload and also in the failing heart. Adriamycin is a cardiotoxic chemotherapeutic agent, and it suppresses the expression of CARP. We compared the expressions of CARP in the myocardium of normotensive rats and spontaneously hypertensive rats (SHRs) that suffered with adriamycin-induced cardiomyopathy. MATERIALS AND METHODS: 36 Wistar-Kyoto rats (WKYs) and 36 SHRs were divided into the adriamycin-administered and saline-administered groups. Adriamycin (2.5 mg/kg) and saline were injected intraperitoneally twice a week for 3 weeks. All the animals were sacrificed 3 weeks after the last injection. Immunohistochemical staining was performed on the left ventricles with using synthesized polyclonal CARP antibody. The positively stained areas were measured by using an image analysis program, and the CARP volume fractions (CaVF) were calculated. RESULTS: CARP was diffusely expressed in the cytoplasm of the myocytes in all the groups. The number of CARP expressing cells was increased in the SHRs. The CaVFs was 5.96+/-5.11% in the WKYs and it was 9.04+/-6.26% in the SHRs (p=0.014). The CaVF was 2.26+/-4.74% in the adriamycin-administered WKYs and it was 1.24+/-4.32% in the adriamycin-administered SHRs (p=0.32). The adriamycin-administered WKYs and SHRs showed significantly decreased CARP expressions, as compared to the saline-administered groups (p<0.001 and p<0.001, respectively). CONCLUSION: These results suggest that CARP is closely related to the pathogenesis of adriamycin-induced cardiomyopathy and it probably plays a pivotal role for the adriamycin cardiac toxicity observed in hypertensive rats.

Cloning of Xenopus laevis TRPV2 by Gene Prediction

TRPV2 is a non-specific cation channel expressed in sensory neurons, and activated by noxious heat. Particularly, TRPV2 has six transmembrane domains and three ankyrin repeats. TRPV2 has been cloned from various species such as human, rat, and mouse. Oocytes of Xenopus laevis - an African clawed frog - have been widely used for decades in characterization of various receptors and ion channels. The functional property of rat TRPV2 was also identified by this oocyte expression system. However, no TRPV2 orthologue of Xenopus laevis has been reported so far. Hence, we have focused to clone a TRPV2 orthologue of Xenopus laevis with the aid of bioinformatic tools. Because the genome sequence of Xenopus laevis is not available until now, a genome sequence of Xenopus tropicalis - a close relative species of Xenopus laevis - was used. After a number of bioinformatic searches in silico, a predicted full-length sequence of TRPV2 orthologue of Xenopus tropicalis was found. Based on this predicted sequence, various approaches such as RT-PCR and 5'-RACE technique were applied to clone a full length of Xenopus laevis TRV2. Consequently, a full-length Xenopus laevis TRPV2 was cloned from heart cDNA.