Publications by authors named "Mohammad Marhabaie"

The Drosophila Pumilio (Pum) and Nanos (Nos) RNA-binding proteins govern abdominal segmentation in the early embryo, as well as a variety of other events during development. They bind together to a compound Nanos Response Element (NRE) present in thousands of maternal mRNAs in the ovary and embryo, including hunchback (hb) mRNA, thereby regulating poly-adenylation, translation, and stability. Many studies support a model in which mRNA recognition and effector recruitment are carried out by distinct regions of each protein.

View Article and Find Full Text PDF

Long-read sequencing can often overcome the deficiencies in routine microarray or short-read technologies in detecting complex genomic rearrangements. Here we used Pacific Biosciences circular consensus sequencing to resolve complex rearrangements in two patients with rare genetic anomalies. Copy number variants (CNVs) identified by clinical microarray -chr8p deletion and chr8q duplication in patient 1, and interstitial deletions of chr18q in patient 2-were suggestive of underlying rearrangements.

View Article and Find Full Text PDF
Article Synopsis
  • De novo variants in the CSNK2A1 gene cause autosomal dominant Okur-Chung neurodevelopmental syndrome (OCNDS), characterized by intellectual disability, global delays, dysmorphic features, and immunological issues.
  • A study of four individuals from three families identified three pathogenic missense variants in CSNK2A1, adding new evidence to the link between these genetic variants and OCNDS.
  • The research highlights that smaller head circumference, including microcephaly, is common but often overlooked in OCNDS, with a significant correlation between variant location in the protein and the presence of microcephaly.
View Article and Find Full Text PDF

The translational repressor Nanos (Nos) regulates a single target, maternal hunchback (hb) mRNA, to govern abdominal segmentation in the early Drosophila embryo. Nos is recruited to sites in the 3' UTR of hb mRNA in collaboration with the sequence-specific RNA-binding protein Pumilio (Pum); on its own, Nos has no binding specificity. Nos is expressed at other stages of development, but very few mRNA targets that might mediate its action at these stages have been described.

View Article and Find Full Text PDF

Common variable immune deficiency (CVID) is a heterogenous group of disorders characterized by varying degrees of hypogammaglobulinemia, recurrent infections, and autoimmunity. Currently, pathogenic variants are identified in approximately 20-30% of CVID cases. Here we report a 3-generation family with autosomal dominant Common Variable Immunodeficiency (CVID) diagnosed in 9 affected individuals.

View Article and Find Full Text PDF

Leigh syndrome is a rare, genetic, and severe mitochondrial disorder characterized by neuromuscular issues (ataxia, seizure, hypotonia, developmental delay, dystonia) and ocular abnormalities (nystagmus, atrophy, strabismus, ptosis). It is caused by pathogenic variants in either mitochondrial or nuclear DNA genes, with an estimated incidence rate of 1 per 40,000 live births. Herein, we present an infant male with nystagmus, hypotonia, and developmental delay who carried a clinical diagnosis of Leigh-like syndrome.

View Article and Find Full Text PDF
Article Synopsis
  • Chromosomal microarray (CMA) testing helps doctors look for genetic problems when there are issues with a fetus or during pregnancy losses.
  • In a study with 842 cases from 2011 to 2020, researchers found that CMA showed significant findings in about 7.8% of prenatal tests and 16.3% of tests from miscarriages.
  • The most common problem detected was trisomy 21, which means having an extra copy of chromosome 21, affecting 7 samples in the study.
View Article and Find Full Text PDF

The Drosophila Pumilio (Pum) and Nanos (Nos) RNA-binding proteins govern abdominal segmentation in the early embryo, as well as a variety of other events during development. They bind together to a compound Nanos Response Element (NRE) present in thousands of maternal mRNAs in the ovary and embryo, including ( ) mRNA, thereby regulating poly-adenylation, translation, and stability. Many studies support a model in which mRNA recognition and effector recruitment are achieved by distinct regions of each protein.

View Article and Find Full Text PDF
Article Synopsis
  • - Somatic mosaicism can lead to neurological disorders, like developmental brain malformations and epilepsy, and is typically thought to happen due to genetic changes after fertilization during fetal development.
  • - This research presents a new idea that some brain mosaicism, specifically in patients with focal epilepsy and extra copies of chromosome 1q, could arise from genetic errors during the formation of reproductive cells.
  • - Analysis revealed that these chromosome 1q gains were present only in the brain tissue of patients and not in their blood or buccal cells, particularly affecting astrocytes, which showed unique gene expressions and inclusions linked to epilepsy.
View Article and Find Full Text PDF

The translational repressor Nanos (Nos) regulates a single target, maternal hunchback (hb) mRNA, to govern abdominal segmentation in the early Drosophila embryo. Nos is recruited specifically to sites in the 3'-UTR of hb mRNA in collaboration with the sequence-specific RNA-binding protein Pumilio (Pum); on its own, Nos has no binding specificity. Nos is expressed at other stages of development, but very few mRNA targets that might mediate its action at these stages have been described.

View Article and Find Full Text PDF

Alterations in the gene have recently emerged as the cause of developmental delay with or without intellectual impairment or behavioral abnormalities (MIM # 619575). The 32 cases currently described in the literature have predominantly de novo alterations in and a wide spectrum of neurodevelopmental abnormalities. Here, we report four patients with novel pathogenic variants identified by research genome sequencing, clinical exome sequencing, and international matchmaking.

View Article and Find Full Text PDF

There is increasing recognition for the contribution of genetic mosaicism to human disease, particularly as high-throughput sequencing has enabled detection of sequence variants at very low allele frequencies. Here, we describe an infant male who presented at 9 mo of age with hypotonia, dysmorphic features, congenital heart disease, hyperinsulinemic hypoglycemia, hypothyroidism, and bilateral sensorineural hearing loss. Whole-genome sequencing of the proband and the parents uncovered an apparent de novo mutation in the X-linked gene.

View Article and Find Full Text PDF

The spider major ampullate (MA) silk exhibits high tensile strength and extensibility and is typically a blend of MaSp1 and MaSp2 proteins with the latter comprising glycine-proline-glycine-glycine-X repeating motifs that promote extensibility and supercontraction. The MA silk from Darwin's bark spider () is estimated to be two to three times tougher than the MA silk from other spider species. Previous research suggests that a unique MaSp4 protein incorporates proline into a novel glycine-proline-glycine-proline motif and may explain MA silk's extraordinary toughness.

View Article and Find Full Text PDF

We investigated the natural variation in silk composition and mechanical performance of the orb-weaving spider Argiope trifasciata at multiple spatial and temporal scales in order to assess how protein composition contributes to the remarkable material properties of spider dragline silk. Major ampullate silk in orb-weaving spiders consists predominantly of two proteins (MaSp1 and MaSp2) with divergent amino acid compositions and functionally different microstructures. Adjusting the expression of these two proteins therefore provides spiders with a simple mechanism to alter the material properties of their silk.

View Article and Find Full Text PDF

Correlated evolution of traits can act synergistically to facilitate organism function. But, what happens when constraints exist on the evolvability of some traits, but not others? The orb web was a key innovation in the origin of >12,000 species of spiders. Orb evolution hinged upon the origin of novel spinning behaviors and innovations in silk material properties.

View Article and Find Full Text PDF