Cell based info Flashcards
Recent genomic analysis of which two bat species revealed what?
Recent genomic analysis of Pteropus alecto and Myotis davidii revealed the absence of the PYHIN gene family.
What do PYHIN proteins do?
The PYHIN proteins play an important role in regulating immune responses and are involved in the intracellular recognition of infectious microbes.
What is an inflammasome?
Large cytosolic multiprotein complexes of the innate immune system that are receptors/sensors of infectious microbes.
They lead to the activation of caspase-1-mediated inflammatory responses, including cleavage and unconventional secretion of proinflammatory cytokines IL-1β and IL-18.
Are inflammasomes present in all organisms?
x
What is the structure of PYHIN proteins?
PYHIN proteins are characterised by two function domains: an N-terminal pyrin domain (PYD) and a C terminal hematopoietic interferon-inducible nuclear (HIN) domain.
Each PYHIN family member possesses an N-terminal Pyrin domain (PYD) and one or more HIN domains classified as either Hin A, Hin B or Hin C.
(https://encyclopedia.pub/entry/6379)
What is NLRP-3?
The NLRP3 inflammasome is a critical component of the innate immune system that mediates caspase-1 activation and the secretion of proinflammatory cytokines IL-1β/IL-18 in response to microbial infection and cellular damage.
What were the scientific methods for identifying the loss of PYHIN genes in bats?
TBLASTN
tblastn search using full-length PYHIN proteins from human and horse
yielded no trace of PYHIN genes in nine of ten bat genomes.
What did they characterise about the locus in the bat genomes?
identified that while the locus was present, the specific PYHIN genes had been removed during evolution
What did their new genomic analysis reveal?
Loss of PYHIN genes in ten bat genomes.
These ten bat species contain representatives across four of five major bat lineages:
family Pteropodidae (Pteropus vampyrus, Pteropus alecto and Eidolon helvum)
and superfamily Rhinolophoidea (Rhinolophus ferrumequinum and Megaderma lyra) under suborder Yinpterochiroptera;
superfamily Vespertilionoidea (Myotis lucifugus, Myotis davidii, Myotis brandtii and Eptesicus fuscus) and
superfamily Noctilionoidea (Pteronotus parnellii) under suborder Yangochiroptera.
Summarise the effect of loss of PYHIN genes
This has ramification for sensing intracellular DNA and activation of inflammasomes.
What is AIM2?
AIM2- Absent in Melanoma 2
In the tblastn, what was unexpectedly identified?
In the 10th genome,a partial sequence matching the first coding exon of AIM2 was revealed in the genome of Parnell’s mustached bat (P. parnellii). This exon encodes the PYRIN domain of AIM2.
In the tblastn why is the unexpected thing probably not functional?
no trace of the other four coding exons of the AIM2 proteins including the HIN domain was found. Importantly, acquisition of a frameshift mutation due to a four-base-pair deletion and several premature stop codons indicates that such bat PYRIN domain is no longer functional
