From: bassam al-kindy Date: Mon, 2 Dec 2013 15:37:14 +0000 (+0100) Subject: add discussion file X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/chloroplast13.git/commitdiff_plain/66d1141218f190b9d6a8997af7d8ef784db3208e add discussion file --- diff --git a/discussion.tex b/discussion.tex new file mode 100644 index 0000000..7f17a7f --- /dev/null +++ b/discussion.tex @@ -0,0 +1,34 @@ +The interesting with the tree produced (especially from DOGMA) is +that organisms resulting from the first endosymbiosis are distributed in +every of the lineage found in the chloroplast genome structure +evolution: with Red Algae chloroplasts together in one lineage, and +Green Algae and Land Plants chloroplasts together in antoher lineage; +while oranisms resulting from secondary endosymbioses are localized in +the tree: both the chloroplasts of Brown Algae and Dinoflagellates +representatives are found exclusively in the lineage also comprising the +Red Algae chloroplasts from which they evolved, while the Euglens +chloroplasts are related to the Green Algae chloroplasts from which they +evolved. This make sense in term of biology and history of lineages and +theories of chloroplasts (and so photosynthetic ability) origins in +different Eucaryotic lineages. +Interestingly, The sole organisms included that possesses a +chloroplast (and so a chloroplastic genome) but that have lost the +photosynthetic ability (being parasitic plant) are found at the base of +the tree, and not together with its related species phylogenetically, +meaning that functional chloroplast genes are evolutionnary constrained +when used in photosynthetic process, but loose rapidly their efficiency +when not used. They are Cuscuta-grovonii an Angiosperm (flowering plant) +at the base of the DOGMA Angiosperm-Conifers branch, and +Epipactis-virginiana also an Angiosperm at the complete base of the tree. +Another interesting result in your work is that Land Plants that +represent single sublineage originating from the large and diverse +lineage of Green Algae in Eucaryots history are present in two different +branches of the DOGMA tree, associated with Green Algae, one branch +comprising the "inferior" Land Plants (mosses and ferns) and the second +comprising the "superior" Land Plants (Conifers and flowering plants). +But independently of their split in two distinct branches of the DOGMA +tree, the Land Plants always show a higher number of functional genes in +their chloroplasts than their related Green Algae, probably meaning that +terrestrial way of life necessitates more functional genes for an +optimal photosynthesis than marine way of life. But a more detailed +analysis of selected genes is necessary to better understad the reasons why.