February language Protein and Institutes -Zayed Shahnewaz
From bees and ants to whales and apes, all animals communicate with each other and none of them had to fight with a regime for their rights to speak the language of their mother but Bangalis had to shed blood on February 21 in 1952. February 21st is declared by UNESCO as International Mother Language Day which now inspires nations to safeguard their mother languages. While thinking about mother language, one can think what human organ is responsible for picking up a language. Is there any language protein or gene which proactively picks ups language and help humans to communicate?
Humans pick up a language which is more than a set of prearranged signals of other animals. Human speech even differs in a physical way from the communication of other animals. It comes from a cortical speech centre which does not respond instinctively, but organises sound and meaning on a rational basis. This section of the brain is unique to humans. When and how the special talent of language developed is impossible to say. But it is generally assumed that its evolution must have been a long process. The origin of language is a hotly contested topic, with some languages tentatively traced back to the Paleolithic. However, archaeological and written records extend the history of language into ancient times and the Neolithic. As we know, genes are often called the blueprint for life, because they tell each of your cells what to do and when to do it: be a muscle, make bone, carry nerve signals, and so on. And how do genes orchestrate all this? They make proteins. In fact, each gene is really just a recipe for a making a certain protein. Researchers have found a gene that could explain why we developed language and speech while our closest living relatives, the chimpanzees, did not. Researchers have identified the first gene directly involved in speech, a discovery that may provide insights into how the brain processes language, and how and when language arose. The gene — FOXP2 — is a transcription factor, meaning it regulates other genes.
Past researches have suggested this gene remained relatively unchanged along mammal evolution until after humans and chimpanzees diverged. And about 200,000 years ago, when modern humans appeared on the scene, scientists think two amino acids changed in FOXP2. The genetic differences among humans and our primate relatives were studied. For example, humans have two amino acid substitutions on a gene called FOXP2 compared to chimpanzees. The changes in this gene became fixed after the evolutionary lineage for humans split from the one for chimpanzees. Earlier studies suggest that the human version of the genes was selected for in our hominid ancestors, possibly because it influenced important aspects of speech and language. People who carry one nonfunctional version of the FOXP2 gene have impairments in the timing of the facial movement required for speech, which suggests that the amino acid substitutions contribute to fine-tuned motor control for muscle movements of the lips, tongue and larynx. So, what are the attributes of FOXP2 gene and why it is called the speech gene? The FOXP2 gene provides instructions for making a protein called forkhead box P2.
As a FOX protein, FOXP2 contains a forkhead-box domain. In addition, it contains a polyglutamine tract, a zinc finger and a leucine zipper. The protein stays attached to the DNA of other proteins and controls their activity through the forkhead-box domain. This protein is a transcription factor, which means that it controls the activity of other genes. It is attached to the DNA of these genes through a region known as a forkhead domain. Researchers suspect that the forkhead box P2 protein may regulate hundreds of genes, although only some of its targets have been identified. This gene also known as CAG repeat protein 44, CAGH44, forkhead/winged-helix transcription factor, SPCH1 or TNRC10. The forkhead box P2 protein is active in several tissues, including the brain, both before and after birth. Studies suggest that it plays important roles in brain development, including the growth of nerve cells (neurons) and the transmission of signals between them. It is also involved in synaptic plasticity, which is the ability of connections between neurons (synapses) to change and adapt to experience over time. Synaptic plasticity is necessary for learning and memory. FOXP2 gene is recently discovered by scientists. The history of discovering this gene is quite interesting. In 1990, Hurst and colleagues reported a unique case of a large three-generation pedigree (called the KE family), half of whose members have a developmental verbal dyspraxia that is inherited in a pattern consistent with an autosomal dominant penetrance. Using standard positional cloning techniques in combination with bioinformatics, Fisher and colleagues performed a genome-wide search for the candidate gene underlying the speech and language disorders in this family.
They mapped the gene locus to the long arm of chromosome 7. In 2001, they finally identified FOXP2 as the gene responsible for this speech and language disorder by further analyzing the breaking point of the genome of a patient, CS, who had similar symptoms to the affected members of the KE family and a translocation between chromosomes 5 and 7. The one point mutation in the FOXP2 gene of the affected members of the KE family is predicted to result in an arginine-to-histidine substitution (R553H) in the forkhead domain of the FOXP2 protein. R553 is invariant among all FOX proteins in species ranging from yeast to humans. This mutation occurred in every affected KE family member, but not in unaffected members, nor in unrelated control subjects. The translocation breakpoint in CS disrupted the gene structure of FOXP2. Furthermore, a nonsense mutation at arginine 328 (R328X) in the FOXP2 gene was found in a family, whose affected members had orofacial dyspraxia.
Therefore, it is likely that the amino acid substitution in FOXP2 protein leads to a loss of function of one copy of the FOXP2 gene and that the remaining copy is insufficient for FOXP2 function. The disease is known as haploinsufficiency. There are several examples of human disease states regarded to be consequence of haploinsufficiency of FOX proteins: mutations in FOXC1, FOXC2, FOXE1 and FOXL2 in humans are associated with congenital hereditary glaucoma, hereditary lymphedema-distichiasis syndrome, thyroid agenesis and ovarian failure with craniofacial anomalies with autosomal dominant inheritance. FOXP2 is expressed in many areas of the brain, including the basal ganglia and inferior frontal cortex, where it is essential for brain maturation and speech and language development. The FOXP2 gene has been implicated in several cognitive functions including; general brain development, language, and synaptic plasticity. The FOXP2 gene region acts as a transcription factor for the forkhead box P2 protein. Transcription factors affect other regions, and the forkhead box P2 protein has been suggested to also act as a transcription factor for hundreds of genes. This prolific involvement opens the possibility that the FOXP2 gene is much more extensive than originally thought.
Other targets of transcription have been researched without correlation to FOXP2. Specifically, FOXP2 has been investigated in correlation with autism and dyslexia, however with no mutation was discovered as the cause. The FOXP2 gene is highly conserved in mammals. The human gene differs from that of non-human primates by the substitution of two amino acids, a threonine to asparagine substitution at position 303 (T303N) and an asparagine to serine substitution at position 325 (N325S). A recent genomic analysis reports the presence of two additional regulatory elements with enhancer function in the telomeric territory separating FOXP2 from its neighbour, MDF1C. These enhancers have been observed to be disrupted in a child with language and speech disorder. The requirement for these two elements in driving proper FOXP2 expression levels was functionally validated in human cell lines. These data lend support to the hypothesis that FOXP2 expression falls under a large array of regulatory elements, which may increase the probability of dysregulation during oncogenic processes.
Learning a language is natural and babies are born with the ability to learn it. All children, no matter which language their parents speak, learn a language in the same way. When babies are born, they can make and hear all the sounds in all the languages in the world. That’s about 150 sounds in about 6500 languages, though no language uses all of those sounds. The sounds a language uses are called phonemes. In this stage, babies learn which phonemes belong to the language they are learning and which don’t.
The ability to recognize and produce those sounds is called “phonemic awareness,” which is important for children learning to read. And between birth to age 5, a child learns at a speed unmatched the rest of his or her life! It is during these years when more than 85 percent of a child’s brain is formed that crucial brain connections are created. Children learn things faster than adults, but what is the best age to learn a new language? Children must start to learn a new language by the age of 10 to achieve the fluency level of a native speaker, a new study has suggested. Scientists believe this is because they have a smaller time frame before their learning abilities begin to weaken around 17, compared with those trying to pick up the same skills before 10. The best time to learn a new language with native-speaker proficiency is by the age of 10. Children under 10 can more easily absorb information and excel in the new language. After the age of 18, however, people may no longer reach the level of proficiency that native speakers have, although they might still be able to learn quickly. In different countries developed or developing, there are some institutional opportunities for learning second language. In developed countries students are offered to learn second languages based on their wish. Primary schools have teachers who are multilingual or expert in a specific second language.
In Bangladesh there are a few institutes which offer to teach foreign languages. English is used here as unofficial second language so people normally try to learn English properly. German, French, Arabic, Chinese, Japanese, Spanish are also popular language learning options in Bangladesh. Institute of Modern Languages (IML) is the prominent institute of University of Dhaka that offers different types of courses for learning these languages. But applicants have to fulfill some criteria before applying on these courses. In other institutes there are age limits to learn foreign languages. But as children can learn a second language more easily than adults; so there must have opportunities for toddlers to learn their desired second languages.