Publications by authors named "Maureen Downing"

 To compare perinatal and neonatal outcomes of dichorionic (DC) and monochorionic (MC) with trichorionic (TC) triplet gestations.  A retrospective cohort study of DC + MC versus TC triplet gestations delivered at a tertiary care hospital from 2009 to 2015. The results include 42 sets of triplets (TC,  = 26; DC + MC,  = 16).

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Targeting of newly synthesized membrane proteins to the endoplasmic reticulum is an essential cellular process. Most membrane proteins are recognized and targeted co-translationally by the signal recognition particle. However, nearly 5% of membrane proteins are 'tail-anchored' by a single carboxy-terminal transmembrane domain that cannot access the co-translational pathway.

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The red fluorescent protein DsRed has been extensively engineered for use as an in vivo research tool. In fast maturing DsRed variants, the chromophore maturation half-time is approximately 40 min, compared to approximately 12 h for wild-type DsRed. Further, DsRed has been converted from a tetramer into a monomer, a task that entailed mutating approximately 20% of the amino acids.

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Group I introns often encode proteins that catalyze site-specific DNA hydrolysis. Some of these proteins have acquired the ability to promote splicing of their cognate intron, but whether these two activities reside in different regions of the protein remains obscure. A crystal structure of I-AniI, a dual function intron-encoded protein, has shown that the protein has two pseudo-symmetric domains of equal size.

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We determined the crystal structure of a bifunctional group I intron splicing factor and homing endonuclease, termed the I-AniI maturase, in complex with its DNA target at 2.6 A resolution. The structure demonstrates the remarkable structural conservation of the beta-sheet DNA-binding motif between highly divergent enzyme subfamilies.

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