fifth monarchy man: Apparently you are not even trying to understand what others have to say.

You keep asking the same questions that indicate you haven't bothered to read or understand the answers provided. For instance,

fifth monarchy man: Do we know these genes have function?

YES. The genes form post-synaptic structures in sponge larvae which have a primitive sensory organ. If you are interested, the following research group website shows the phylogenetic relationship and has images of sponge larvae.

Adamska Group, Developmental Signalling in Marine Sponges: The pigment ring at the posterior pole is a sensory organ and provides steering in response to light… Analysis of the Amphimedon genome and expression studies throughout embryonic development demonstrate that all major metazoan signalling pathways are used during sponge embryogenesis.

fifth monarchy man: Are they vital?

By "vital", do you mean that if we artificially knock out the function, the organism is no longer viable in the lab?

Apparently you are not even trying to understand what others have to say. That is sad as I would have liked to explore this paper further with a frontloading critic.

I only suggest that you look at my questions and your answers. I asked what I thought were specific questions and you simply repeated the same non responses.

They are not related at all as far as I can tell to what I asked.
It’s like you are involved in a different conversation than me.
Oh well

Peace

Zachriel: Even if not, the genes involved are expressed,

fifth monarchy man: Not expressed in sponges for this purpose as far as I know

The original post cited LiveScience and indicates the researchers *looked* for "the molecular building blocks of nerves, or what may be called the nerve's ancestor the proto-neuron." And they found them. Then in my very first comment, I cited the paper in Current Biology that says, "During Amphimedon development, a field of subepithelial cells expresses the Notch receptor, its ligand Delta, and a sponge bHLH gene, AmqbHLH1." I repeated this later saying, "They're expressed in everything from sponges to sparrows. In particular, the Notch receptor is expressed during development in subepithelial sponge cells." Furthermore, they are expressed in free-swimming sponge larvae as post-synaptic structures!

fifth monarchy man: That is the question I have are these genes expressed in this process. Are they vital?

They're expressed. That means they are subject to selection. As to empirical testing for whether they are "vital" …

fifth monarchy man: If they do is it the kind of vital function that would explain the ultraconservation we see here.

We've talked about this too. These genes form the foundation of later developments in the nervous system. They're conserved because everything else comes to depend on them. Thought Provoker even repeated the basic argument, to which I made a few clarifying remarks.

fifth monarchy man: Think about it, these genes remained ultrastable for 500 million years more than the time it took for the first chordate to become the first Caesar. You would expect evolution to at a least do a little tweaking in all that time.

From the same study, "Phylogenetic analysis suggests that AmqbHLH1 is descendent from a single ancestral bHLH gene that later duplicated to produce the atonal/neurogenin-related bHLH gene families, which include most bilaterian proneural genes. "

I am as giddy as a school girl.

here is a juicy quote:

The most rapidly evolving sequence they identified, termed HACNS1, is highly conserved among vertebrate species but has accumulated variations in 16 base pairs since the divergence of humans and chimpanzees some 6 million years ago. This was especially surprising, as the human and chimpanzee genomes are extremely similar overall, Noonan said.

end quote:

These are noncoding genes thought until recently to be Junk!!!!! Why in the world are they ultra conserved and then suddenly for no known reason become hyper evolving just in time for us.

It's like a neon sign flashing frontloaded

All that is left is to do some research to see if all that is necessary for our all important dexterityis to turn on these ultraconserved/hyperevolving noncoding genes

but wait.

Quote:

However, Noonan stressed that it is still unknown whether HACNS1 causes changes in gene expression in human limb development or whether HACNS1 would create human-like limb development if introduced directly into the genome of a mouse

end quote

I can’t wait to hear Zach say MET predicted this all along

Peace

I think you are missing Doug's point. Sponges may have diverged *after* Ctenophora, and Ctenophora have a primitive sub-epidermal nervous system.

No, I get his point but it is irrelevant to the subject of this thread. The surprising thing is not how this information got in the sponge but how it was ultraconserved and how it could be so easily turned on in an organism that needed it

Even if not, the genes involved are expressed,

Not expressed in sponges for this purpose as far as I know

and while sponges may not have nerves, they have various levels of intercellular communication and there is some evidence of sensory capability in sponge larvae.

That is the question I have are these genes expressed in this process. Are they vital? I don’t know.
Do you? (please provide a reference)

It's not surprising that a gene is conserved if it has a function. That's the expected pattern.

A couple of questions
1) Do we know these genes have function? (please provide a reference)
2) If they do is it the kind of vital function that would explain the ultraconservation we see here.

Think about it, these genes remained ultrastable for 500 million years more than the time it took for the first chordate to become the first Caesar. You would expect evolution to at a least do a little tweaking in all that time.

Peace

There is another paper about the hox gene family at PloS

http://www.plosone.org/article...

which gives insights to the genome and the connection between the simplest of metazoa.

I wonder if the front loaders and EAMlers ever considered looking at this very simple creature

Nature. 2008 Aug 21;454(7207):955-60

The abstract:

As arguably the simplest free-living animals, placozoans may represent a primitive metazoan form, yet their biology is poorly understood. Here we report the sequencing and analysis of the approximately 98 million base pair nuclear genome of the placozoan Trichoplax adhaerens. Whole-genome phylogenetic analysis suggests that placozoans belong to a 'eumetazoan' clade that includes cnidarians and bilaterians, with sponges as the earliest diverging animals. The compact genome shows conserved gene content, gene structure and synteny in relation to the human and other complex eumetazoan genomes. Despite the apparent cellular and organismal simplicity of Trichoplax, its genome encodes a rich array of transcription factor and signalling pathway genes that are typically associated with diverse cell types and developmental processes in eumetazoans, motivating further searches for cryptic cellular complexity and/or as yet unobserved life history stages.

It might be intresting to follow this up.

All the best
Karla

Onur Sakarya, et al., A Post-Synaptic Scaffold at the Origin of the Animal Kingdom, PLoS One 2007:

Highly conserved protein interaction motifs and co-expression in sponges of multiple proteins whose homologs interact in eumetazoan synapses indicate that a complex protein scaffold was present at the origin of animals, perhaps predating nervous systems. A relatively small number of crucial innovations to this pre-existing structure may represent the founding changes that led to a post-synaptic element.

Doug: So the comb jelly predates the sponge and the comb jelly would have nervous tissue.

fifth monarchy man: It’s my understanding that the sponge does not have nervous tissue, it has the genetic building blocks for nerves but these are unexpressed for that purpose.

I think you are missing Doug's point. Sponges may have diverged *after* Ctenophora, and Ctenophora have a primitive sub-epidermal nervous system. Even if not, the genes involved are expressed, and while sponges may not have nerves, they have various levels of intercellular communication and there is some evidence of sensory capability in sponge larvae.

fifth monarchy man: The surprising part of this story is the fact that these genes are ultraconserved and that they can be turned on when inserted into an animal with a need for them.

It's not surprising that a gene is conserved if it has a function. That's the expected pattern.

Zachriel: Oh, you mentioned that your statement was scientifically meaningless. Nevermind, then. As this thread is about a scientific paper on sponges, I'll just ignore your comment.

kornbelt888: Scientifically meaningless does not indicate absolutely meaningless.

I agree. But this was a thread about a scientific paper. And from Bradford's later comments, I think he means them to have scientific relevance.

kornbelt888: Remember, this is Telic Thoughts. Not limited to mere science talk here. There are plenty of other fora for that.

Telic Thoughts is an independent blog about intelligent design. Most definitions of "intelligent design" include a scientific component, that design can be empirically detected, as opposed to merely a metaphysical belief or a spiritual experience of meaningfulness and awe.

kornbelt888: You don't seem to care for telic speculation.

I enjoy speculation, including scientific speculation. That's how many great hypotheses are developed. Einstein imagined he was riding a beam of light and wondered what he would see. Kekulé dreamed of a snake swallowing its tail.

A scientific speculation takes the form of a conditional, but instead of {If P then Q} like a well-formed hypothesis, we have {If P then ?}. So, we might speculate thusly.

{If} aliens seeded various nebula with life, like a gardener spreading seeds, {then} even though they might not be able to predict with precision what any particular nebula might do, or even if it would be fruitful at all, but through experience might know that a certain percentage would result in intelligent life. Or maybe intelligence is just a weed to be pulled out periodically, especially when they start sending out spores (spaceships). Determining this requires knowledge of the means and motives of the gardeners.

kornbelt888: But that's very purpose of this Telic Thoughts. (Hence the name.) One wonders why you participate here.

One wonders why you would post your speculations if you weren't inviting comment.