Different gene knockout/transgenic mouse models manifesting persistent fetal vasculature: Are integrins to blame for this pathological condition?

Persistent fetal vasculature (PFV) occurs as a result of a failure of fetal vasculature to undergo normal programmed involution. During development, before the formation of retinal vessels, the lens and the inner retina are nourished by the hyaloid vasculature. Hyaloid vessels extend from the optic nerve and run through the vitreous to encapsulate the lens.

A Novel Organ Culture Model to Quantify Collagen Remodeling in Tree Shrew Sclera.

Increasing evidence suggests that unknown collagen remodeling mechanisms in the sclera underlie myopia development. We are proposing a novel organ culture system in combination with two-photon fluorescence imaging to quantify collagen remodeling at the tissue- and lamella-level. Tree shrew scleral shells were cultured up to 7 days in serum-free media and cellular viability was investigated under: (i) minimal tissue manipulations; (ii) removal of intraocular tissues; gluing the eye to a washer using (iii) 50 μL and (iv) 200 μL of cyanoacrylate adhesive; (v) supplementing media with Ham's F-12 Nutrient Mixture; and (vi) culturing eyes subjected to 15 mmHg intraocular pressure in our new bioreactor.

CRYβA3/A1-Crystallin Knockout Develops Nuclear Cataract and Causes Impaired Lysosomal Cargo Clearance and Calpain Activation.

βA3/A1-crystallin is an abundant structural protein of the lens that is very critical for lens function. Many different genetic mutations have been shown to associate with different types of cataracts in humans and in animal models. βA3/A1-crystallin has four Greek key-motifs that organize into two crystallin domains.

Interaction of βA3-Crystallin with Deamidated Mutants of αA- and αB-Crystallins.

Interaction among crystallins is required for the maintenance of lens transparency. Deamidation is one of the most common post-translational modifications in crystallins, which results in incorrect interaction and leads to aggregate formation. Various studies have established interaction among the α- and β-crystallins.

Molecular mechanism of formation of cortical opacity in CRYAAN101D transgenic mice.

Purpose: The CRYAAN101D transgenic mouse model expressing deamidated αA-crystallin (deamidation at N101 position to D) develops cortical cataract at the age of 7 to 9 months. The present study was carried out to explore the molecular mechanism that leads to the development of cortical opacity in CRYAAN101D lenses.

Methods: RNA sequence analysis was carried out on 2- and 4-month-old αA-N101D and wild type (WT) lenses.

The lipoprotein La7 contributes to Borrelia burgdorferi persistence in ticks and their transmission to naïve hosts.

La7, an immunogenic outer membrane lipoprotein of Borrelia burgdorferi, produced during infection, has been shown to play a redundant role in mammalian infectivity. Here we show that La7 facilitates pathogen survival in all tested phases of the vector-specific spirochete life cycle, including tick-to-host transmission. Unlike wild type or la7-complemented isolates, isogenic La7-deficient spirochetes are severely impaired in their ability to persist within feeding ticks during acquisition from mice, in quiescent ticks during larval-nymphal inter-molt, and in subsequent pathogen transmission from ticks to naïve hosts.

Portal-large terminase interactions of the bacteriophage T4 DNA packaging machine implicate a molecular lever mechanism for coupling ATPase to DNA translocation.

DNA packaging by double-stranded DNA bacteriophages and herpesviruses is driven by a powerful molecular machine assembled at the portal vertex of the empty prohead. The phage T4 packaging machine consists of three components: dodecameric portal (gp20), pentameric large terminase motor (gp17), and 11- or 12-meric small terminase (gp16). These components dynamically interact and orchestrate a complex series of reactions to produce a DNA-filled head containing one viral genome per head.

The structure of the phage T4 DNA packaging motor suggests a mechanism dependent on electrostatic forces.

Viral genomes are packaged into "procapsids" by powerful molecular motors. We report the crystal structure of the DNA packaging motor protein, gene product 17 (gp17), in bacteriophage T4. The structure consists of an N-terminal ATPase domain, which provides energy for compacting DNA, and a C-terminal nuclease domain, which terminates packaging.