Month: September 2022

SO ENDS this first weekend considering angiosperm reproduction, including the journey of the male sperm in the pollen tube and subsequent double fertilization. While the transition of plants to dry land was a step that allowed great radiation of new species and success for flowering plants, the problems of reproduction on dry land were solved in over-complicated ways due to the nature of evolution: taking something adapted to one system and wrenching it into another system. View in LinkedIn

DE NOVO GENE BIRTH. "The birth of de novo genes encoding functional proteins involves two important steps: the acquisition of an ORF and the addition of regulatory signals needed for transcription." (ORF = open reading frame). http://www.sciencedirect.com/science/article/pii/S0168952515000347 View in LinkedIn

FIRST STEP IN CREATING NEW GENES. "In order for non-coding DNA to begin to function as a protein-coding gene, an ORF must originate, the DNA must be transcribed and the mRNA translated, and the protein should ultimately become integrated into the cellular processes."(ORF = open reading frame). https://lnkd.in/dPqZs3m View in LinkedIn

OPEN READING FRAMES (ORFs). "We searched the human genome for ORFs and found over 13.5 million ORFs of at least 33 codons long, compared to over 47,000 of the same length threshold in yeast (including annotated genes)." https://lnkd.in/dPqZs3m View in LinkedIn

JUNIOR PROTEIN. "The potential protein of a novel ORF can be considered an arbitrary sequence, as opposed to one that has been refined by natural selection. It has been shown that an arbitrary sequence can contain selectable variation, at least in some circumstances. If not expressed, neither the favourable nor the unfavourable ORFs in the genome will have the opportunity to be improved or removed by selection." (ORF = open reading frame). https://lnkd.in/dPqZs3m View in LinkedIn

PROTO-GENES. "It is now widely accepted that a large fraction of the genome is being transcribed, with many long-noncoding RNA molecules being generated. Interestingly, a considerable fraction of these RNAs are also associated with ribosomes, suggesting they are actively translated. Such short peptides form proto genes, which can be subject to selection." http://www.sciencedirect.com/science/article/pii/S0168952515000347 View in LinkedIn

EXPRESSION FIRST. "Through the acquisition of new mutations, proto genes can grow and result in functional de novo genes. Alternatively, it is also possible that the full-length transcript is initially interrupted by stop codons, but new mutations generate the full-length ORF of the de novo gene. This model is strongly supported by a range of studies that found transcription preceded the emergence of an ORF and translation." (ORF = open reading frame). http://www.sciencedirect.com/science/article/pii/S0168952515000347 View in LinkedIn

CONSTANT GENE TURNOVER. "Genes are perpetually added to and deleted from genomes during evolution. Thus, it is important to understand how new genes are formed and evolve as critical components of the genetic systems determining the biological diversity of life." https://lnkd.in/d__2shu View in LinkedIn

NEW GENE INTEGRATION. "Two competing hypotheses about the process of de novo gene birth are discussed as well as the high death rate of de novo genes. Despite the high death rate, some de novo genes are retained and remain functional, even in distantly related species, through their integration into gene networks." http://www.sciencedirect.com/science/article/pii/S0168952515000347 View in LinkedIn

FEW AND SMALL. "De novo genes arise from previously noncoding DNA, are short, and are expressed at low levels. These features frequently raise doubts about the biological significance of de novo genes. In light of these concerns, several approaches have been used to distinguish true de novo genes from random noise." https://lnkd.in/d4n2asc View in LinkedIn