Advancements in Viral Gene Therapy for Gaucher Disease.

Gaucher disease, an autosomal recessively inherited lysosomal storage disorder, results from biallelic mutations in the GBA1 gene resulting in deficient activity of the enzyme glucocerebrosidase. In Gaucher disease, the reduced levels and activity of glucocerebrosidase lead to a disparity in the rates of formation and breakdown of glucocerebroside and glucosylsphingosine, resulting in the accumulation of these lipid substrates in the lysosome. This gives rise to the development of Gaucher cells, engorged macrophages with a characteristic wrinkled tissue paper appearance. There are both non-neuronopathic (type 1) and neuronopathic (types 2 and 3) forms of Gaucher disease, associated with varying degrees of severity. The visceral and hematologic manifestations of Gaucher disease respond well to both enzyme replacement therapy and substrate reduction therapy. However, these therapies do not improve the neuronopathic manifestations, as they cannot cross the blood-brain barrier. There is now an established precedent for treating lysosomal storage disorders with gene therapy strategies, as many have the potential to cross into the brain. The range of the gene therapies being employed is broad, but this review aimed to discuss the progress, advances, and challenges in developing viral gene therapy as a treatment for Gaucher disease.

Using CRISPR/Cas9 to identify genes required for mechanosensory neuron development and function.

Tunicates are marine, non-vertebrate chordates that comprise the sister group to the vertebrates. Most tunicates have a biphasic lifecycle that alternates between a swimming larva and a sessile adult. Recent advances have shed light on the neural basis for the tunicate larva's ability to sense a proper substrate for settlement and initiate metamorphosis. Work in the highly tractable laboratory model tunicate Ciona robusta suggests that sensory neurons embedded in the anterior papillae transduce mechanosensory stimuli to trigger larval tail retraction and initiate the process of metamorphosis. Here, we take advantage of the low-cost and simplicity of Ciona by using tissue-specific CRISPR/Cas9-mediated mutagenesis to screen for genes potentially involved in mechanosensation and metamorphosis, in the context of an undergraduate 'capstone' research course. This small screen revealed at least one gene, Vamp1/2/3, which appears crucial for the ability of the papillae to trigger metamorphosis. We also provide step-by-step protocols and tutorials associated with this course, in the hope that it might be replicated in similar CRISPR-based laboratory courses wherever Ciona are available.

Using CRISPR/Cas9 to identify genes required for mechanosensory neuron development and function.

Tunicates are marine, non-vertebrate chordates that comprise the sister group to the vertebrates. Most tunicates have a biphasic lifecycle that alternates between a swimming larva and a sessile adult. Recent advances have shed light on the neural basis for the tunicate larva's ability to sense a proper substrate for settlement and initiate metamorphosis. Work in the highly tractable laboratory model tunicate Ciona robusta suggests that sensory neurons embedded in the anterior papillae of transduce mechanosensory stimuli to trigger larval tail retraction and initiate the process of metamorphosis. Here, we take advantage of the low-cost and simplicity of Ciona by using tissue-specific CRISPR/Cas9-mediated mutagenesis to screen for genes potentially involved in mechanosensation and metamorphosis, in the context of an undergraduate "capstone" research course. This small screen revealed at least one gene, Vamp1/2/3 , that appears crucial for the ability of the papillae to trigger metamorphosis. We also provide step-by-step protocols and tutorials associated with this course, in the hope that it might be replicated in similar CRISPR-based laboratory courses wherever Ciona are available.

Multiple sites on SARS-CoV-2 spike protein are susceptible to proteolysis by cathepsins B, K, L, S, and V.

SARS-CoV-2 is the coronavirus responsible for the COVID-19 pandemic. Proteases are central to the infection process of SARS-CoV-2. Cleavage of the spike protein on the virus's capsid causes the conformational change that leads to membrane fusion and viral entry into the target cell. Since inhibition of one protease, even the dominant protease like TMPRSS2, may not be sufficient to block SARS-CoV-2 entry into cells, other proteases that may play an activating role and hydrolyze the spike protein must be identified. We identified amino acid sequences in all regions of spike protein, including the S1/S2 region critical for activation and viral entry, that are susceptible to cleavage by furin and cathepsins B, K, L, S, and V using PACMANS, a computational platform that identifies and ranks preferred sites of proteolytic cleavage on substrates, and verified with molecular docking analysis and immunoblotting to determine if binding of these proteases can occur on the spike protein that were identified as possible cleavage sites. Together, this study highlights cathepsins B, K, L, S, and V for consideration in SARS-CoV-2 infection and presents methodologies by which other proteases can be screened to determine a role in viral entry. This highlights additional proteases to be considered in COVID-19 studies, particularly regarding exacerbated damage in inflammatory preconditions where these proteases are generally upregulated.

Female rat transcriptome response to infraorbital nerve transection differs from that of males: RNA-seq.

The effects of infraorbital nerve (ION) transection on gene expression in the adult female rat barrel cortex were investigated using RNA sequencing. After a 24-hour survival duration, 28 genes were differentially regulated by ION transection. Differentially expressed genes suggest microglial activity, increased retrograde ciliary transport, and a decrease in inhibition. These changes may be functionally comparable to changes in the male barrel cortex, where changes in genes related to morphology, neuronal activity, and neuronal excitability were observed. However, the patterns in changes in gene expression are vastly different between male and female rats. The results strongly caution against the practice of generalizing data from one sex to both sexes. This cautionary note has potentially profound implications for a range of research lines, including substance abuse and stress, both research domains in which subjects have been predominantly males. Future research needs to employ sex as a classification variable, as sex differences can generally be expected. Future research is also needed to confirm that changes in gene expression observed with RNA-seq correlate with changes in protein expression. J. Comp. Neurol. 525:140-150, 2017. © 2016 Wiley Periodicals, Inc.

Fetal intracranial calcification: pseudo-TORCH phenotype and discussion of related phenotypes.

Fetal intracranial calcification (ICC) noted during antenatal imaging poses a diagnostic challenge. Although this presentation is most commonly associated with intrauterine infection, non-infectious causes of fetal ICC have been reported and include metabolic, genetic, or hemodynamic conditions. We report on a patient with antenatally detected extensive ICC, in whom postnatal imaging revealed a distinctive band-like ICC with abnormal gyral pattern and a negative serology for TORCH infections. Such a constellation of findings have been previously described under the terminology of "pseudo-TORCH phenotype," and we posit that our patient represents this entity. Our patient had unreported dysmorphic features, which expands the phenotypic spectrum of this recently described heterogenous condition. In addition we report on the progression of the phenotype both clinically and radiologically. In view of the limited information available for the differential diagnosis of fetal ICC, we also review the available literature on this topic.

Adams-Oliver syndrome: Additions to the clinical features and possible role of BMP pathway.

We report on a patient with Adams-Oliver syndrome, a condition characterized by scalp and limb defects. In addition we noted in our patient a significant delay in the bone age and an abnormal distal phalanx in one of her fingers manifesting clinically as a broad finger tip. Both these features hitherto unreported add to the phenotypic spectrum of the condition. The underlying etiopathogenesis of this condition has remained in the domain of hypothesis, with none being conclusive. Based on the characteristic features of AOS and our report of delayed bone age, we postulate a role played by the bone morphogenetic protein pathway in the causation of this enigmatic condition. In the background of this postulation and the report of an unusual hand anomaly, a literature review on the various pathogenetic mechanisms and anomalies of the hand reported in AOS is presented.

'Thinfat' phenotype in newborns.

OBJECTIVE: The objectives of the study was to know whether the 'thinfat' phenotype exists in newborns, in Central Karnataka and to correlate various factors that contribute to this peculiar phenotype, with emphasis on genetic and maternal environmental factors. METHODS: For 1000 consecutive singleton term newborns, weight, length, head, mid arm, abdominal circumferences, biceps and subscapular skinfolds were measured at birth and compared with measurements of white Caucasian babies born in Southampton UK and Mysore babies at birth. RESULTS: The Davangere babies were significantly smaller in all measurements at birth (p < 0.001) compared to Southampton babies. The deficit varied according to the measurements; It was greatest for birth weight (-1.6 SD, CI -3.0, -0.2), mid arm circumference (-2.0 SD, CI -3.3, -0.8), head circumference (-1.8 SD, CI -3.1, -0.5) and least for length (-0.4 SD, CI -1.9, 1.1) and subscapular skin fold (-0.3 SD, CI -0.25, -0.12). Predictors of skinfold thickness were maternal body mass index (p < 0.05), maternal mid arm circumference (p < 0.001) and consanguinity (p < 0.05). CONCLUSION: Despite being small, truncal adiposity was present in Davangere neonates confirming the 'thinfat' phenotype. The role of consanguinity in other words, the role of genes, is important in determining this 'thinfat' phenotype in newborns.

Absence of Wharton's jelly around the umbilical arteries.

Wharton's jelly is a specialized tissue which acts as supportive and protective structure substituting for the adventitia of the umbilical vessels. Absence of Wharton's jelly around the umbilical arteries is very rare and an unusual cause of perinatal mortality. We report a case of absent Wharton's jelly around the umbilical arteries with patent vitellointestinal duct--a rare association.

Baseline Widal titres in healthy children.

OBJECTIVE: To determine the baseline Widal titres in apparently healthy children in Davangere. METHODS: Cross-sectional study was done on 250 children. Widal titers were found using tube agglutination test. RESULTS: Out of 250,64.2% had a titre of less than 1:20,22.4% had a titre equal to 1:20,9.6% had a titre of 1:40 and 3.6% had a titre of 1:80 to 'O' antigen and 67.2% had a titre of less than 1:20, 21.2% had a titre equal to 1:20, 8% had a titre of 1:40 and 3.6% had a titre of 1:80 to 'H' antigen of S. enterica subsp. enterica ser. Typhi. No children in age group 6 months-2 years had a titre of 1:80 to either antigen. All children in this age group had a titre of less than 1:20 to AH antigen and older children had a titre upto 1:40 dilution. CONCLUSION: Baseline titres for either S. enterica subsp. enterica ser. Typhi antigen in 6 month-2 year was 1:40 and older children was 1:80. Baseline titres for H antigen of S. enterica subsp. enterica ser. Paratyphi A in 6 month-2 year was less than 1:20 and for older children was 1:40 dilution.

Kallmann's syndrome.

Kallmann's syndrome is a rare genetic disorder due to abnormal migration of olfactory axons and gonadotropin releasing hormone producing neurons, characterized by hypogonadism and anosmia. The prevalence of Kallmann's syndrome is 1:10,000 to 1:60,000 with a male to female ratio of 5:1. The inheritance of Kallmann's syndrome may be X-linked, autosomal recessive or autosomal dominant with variable penetrance, mutation involving KAL-1 and KAL-2 gene respectively. We report a case of Kallmann's syndrome in a 19-year-old boy with characteristic clinical, biochemical and MRI findings.